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<title>Climate Change: Impact on Crop Vegetation and Land Use</title></titleStmt>

<publicationStmt><distributor>BASE and Oxford Text Archive</distributor>


<availability><p>The British Academic Spoken English (BASE) corpus was developed at the Universities of Warwick and Reading, under the directorship of Hilary Nesi (Centre for English Language Teacher Education, Warwick) and Paul Thompson (Department of Applied Linguistics, Reading), with funding from BALEAP, EURALEX, the British Academy and the Arts and Humanities Research Board. The original recordings are held at the Universities of Warwick and Reading, and at the Oxford Text Archive and may be consulted by bona fide researchers upon written application to any of the holding bodies. The BASE corpus is freely available to researchers who agree to the following conditions:</p>

<p>1. The recordings and transcriptions should not be modified in any


<p>2. The recordings and transcriptions should be used for research purposes only; they should not be reproduced in teaching materials</p>

<p>3. The recordings and transcriptions should not be reproduced in full for a wider audience/readership, although researchers are free to quote short passages of text (up to 200 running words from any given speech event)</p>

<p>4. The corpus developers should be informed of all presentations or

publications arising from analysis of the corpus</p><p> Researchers should acknowledge their use of the corpus using the following form of words: The recordings and transcriptions used in this study come from the British Academic Spoken English (BASE) corpus, which was developed at the Universities of Warwick and Reading under the directorship of Hilary Nesi (Warwick) and Paul Thompson (Reading). Corpus development was assisted by funding from the Universities of Warwick and Reading, BALEAP, EURALEX, the British Academy and the Arts and Humanities Research Board. </p></availability>




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<langUsage><language id="en">English</language>



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<item n="speechevent">Lecture</item>

<item n="acaddept">Plant Sciences</item>

<item n="acaddiv">ls</item>

<item n="partlevel">UG2</item>

<item n="module">Physical Ecology</item>







<u who="nm1359">

this week i'm i'm going to <pause dur="0.4"/> just basically one lecture which comes on from from last week's <pause dur="0.7"/> session <pause dur="0.6"/> # <pause dur="0.5"/> last week we looked at climatic change <pause dur="0.3"/> sort of <pause dur="0.7"/> observation measurements <pause dur="0.3"/> today i want to sort of <pause dur="0.6"/> link in <pause dur="0.7"/> with that the implications for crops vegetation and land use <pause dur="0.4"/> and it will hopefully tie together some of the bits of the course that we've been <pause dur="0.3"/> doing with this this term <pause dur="0.4"/> # <pause dur="0.2"/> so that will be one lecture <pause dur="0.4"/> and then <pause dur="0.5"/> there'll be a pause <pause dur="0.3"/> and i'll tell you about the exam questions <pause dur="0.2"/> # and i'm happy to deal with any questions over over the course as a whole <pause dur="0.3"/> does

that sound okay <pause dur="2.4"/> okay so <pause dur="1.0"/> there's the title climate change implications of crops vegetation and land use <pause dur="1.1"/> # <pause dur="3.2"/> diagram about climatic change in general <pause dur="0.6"/> # and we've done part of this over the last few weeks <pause dur="0.5"/> # <pause dur="1.4"/> that basically <pause dur="0.2"/> we talked first of all about emissions and concentrations of greenhouse gases and and how <pause dur="0.8"/> man's activities on the earth's surface <pause dur="0.5"/> and agricultural activities land use changes et cetera were affecting that <pause dur="0.8"/> # then last week we talked <pause dur="0.5"/> a bit about <pause dur="0.2"/> the effects on climatic change <pause dur="0.3"/> the observed changes in temperature <pause dur="0.2"/> sea level rise et cetera <pause dur="0.4"/> # <pause dur="1.7"/> so today i'm going a little bit across to look at the effects of impacts on on <pause dur="0.4"/> human natural systems <pause dur="0.5"/> # <pause dur="0.2"/> we can actually have a whole module on that <pause dur="1.2"/> no doubt at all very important topic <pause dur="0.4"/> # <pause dur="0.2"/> but i've basically <pause dur="0.2"/> restricted myself really to # bits about food and agriculture and and crops <pause dur="1.0"/> #

<pause dur="0.7"/> obviously there is a circle here <kinesic desc="indicates board on wall" iterated="n"/> <pause dur="0.3"/> and we're not going to <pause dur="0.3"/> really get into how we adapt and <pause dur="0.2"/> affect and feedback into climate i'm going to <kinesic desc="indicates board on wall" iterated="n"/> concentrate on the effects <pause dur="0.4"/> of climatic change on on those <pause dur="0.3"/> uses <pause dur="0.5"/> just to summarise a bit these are the slides we had last week # <pause dur="1.0"/> # <pause dur="1.3"/> the I-P-C-C <pause dur="0.2"/> interdepartmental panel sort of prediction for climate change <pause dur="0.5"/> # for the next hundred years <pause dur="0.3"/> and <pause dur="0.8"/> # the thing that we're sure <pause dur="0.2"/> about are that C-O-two <trunc> concentra </trunc> concentrations are going to rise <pause dur="0.3"/> # over the next hundred years <pause dur="0.6"/> and <pause dur="0.7"/> certainly from <pause dur="0.8"/> where we are at the moment about three-sixty-five parts per million <pause dur="0.4"/> to a minimum of about five-hundred <pause dur="0.2"/> and possibly up to

eight-hundred <kinesic desc="indicates board on wall" iterated="n"/> pause dur="0.8"/> # <pause dur="1.1"/> so that's <pause dur="0.3"/> going to be something that's going to affect plants and vegetation <pause dur="0.5"/> completely so <pause dur="0.2"/> C-O-two change is the one thing to think about <pause dur="0.7"/> # <pause dur="0.9"/> and then there's going to be changes in temperature <pause dur="0.2"/> again with great uncertainties <pause dur="0.4"/> # <pause dur="0.7"/> up to three or four degrees depending upon <trunc> gra </trunc> # green house gas emissions <pause dur="0.6"/> # <pause dur="0.2"/> and <kinesic desc="indicates board on wall" iterated="n"/> a corresponding increase in sea level rise <pause dur="0.6"/> but <pause dur="0.2"/> really <pause dur="0.2"/> for the point of view of <pause dur="0.5"/> # <pause dur="0.4"/> vegetation we <unclear> got to </unclear> concentrate on <pause dur="0.6"/> C-O-two <pause dur="0.2"/> temperature <pause dur="0.2"/> and <pause dur="0.5"/> the consequent effects upon rain fall and water

balance <pause dur="1.3"/> # <pause dur="0.4"/> again this is just a recap from last week <pause dur="0.3"/> just to emphasise the changes that <pause dur="0.6"/> are likely to happen in the next hundred years or so <pause dur="0.5"/> and we are talking <pause dur="0.3"/> typically around three or four degrees increase in mean temperature in in our latitudes <pause dur="0.7"/> with the position about rainfall <pause dur="0.5"/> very much less clear <pause dur="2.2"/> okay so <pause dur="0.5"/> think now back to <trunc> photosynth </trunc> # to carbon dioxide and photosynthesis <pause dur="0.6"/> # <pause dur="1.0"/> and <pause dur="0.4"/> obviously <pause dur="0.5"/> as as i'm sure most of you're aware <pause dur="1.7"/> # <trunc> s </trunc> <pause dur="0.5"/> photosynthesis can be restricted by carbon dioxide <pause dur="0.6"/> and if you take <pause dur="0.6"/> most <pause dur="0.3"/> crop plants like wheat <kinesic desc="indicates board on wall" iterated="n"/> pause dur="0.5"/> which have sort of C-three <pause dur="0.7"/> # metabolism for <pause dur="0.2"/> fixing carbon in in photosynthesis <pause dur="0.5"/> then <pause dur="0.7"/> there's a relationship <pause dur="0.4"/> between the rate of carbon dioxide fixation photosynthesis

<pause dur="0.2"/> and <pause dur="0.4"/> the C-O-two level <pause dur="0.2"/> but this is inside the leaf <pause dur="0.5"/> # <pause dur="0.3"/> <kinesic desc="indicates board on wall" iterated="n"/> and basically as the C-O-two level inside the leaf increases <pause dur="0.3"/> photosynthesis increases <kinesic desc="indicates board on wall" iterated="n"/> <pause dur="0.6"/> # the C-O-two level inside the leaf also links <pause dur="0.4"/> with the C-O-two level outside <pause dur="0.3"/> so basically <pause dur="1.0"/> for C-three plants which are most of the crop plants of the world <pause dur="0.4"/> an increase in <pause dur="0.2"/> carbon dioxide <pause dur="0.6"/> in the atmosphere is going to give an increase rate of photosynthesis <pause dur="0.8"/> # <pause dur="0.2"/> that's not actually true for C-four <kinesic desc="indicates board on wall" iterated="n"/> plants <pause dur="0.4"/> # which are mainly that as you know <pause dur="0.3"/> tropical grasses sorghum maize <pause dur="0.3"/> millet et cetera being the main crops <pause dur="0.5"/> #

<pause dur="0.3"/> they have a sort of slightly strange <pause dur="0.5"/> or different i should say photosynthetic mechanism <pause dur="0.2"/> where they <pause dur="0.5"/> # <pause dur="1.2"/> effectively <pause dur="0.2"/> accumulate <pause dur="0.6"/> # carbon dioxide close to the sight of of photosynthesis <pause dur="0.4"/> # <pause dur="0.3"/> and the external <pause dur="0.9"/> concentration really doesn't make <pause dur="0.2"/> very much difference <pause dur="1.8"/> so <pause dur="1.5"/> increasing carbon dioxide in the atmosphere will increase photosynthesis by C-three plants but not by <pause dur="0.3"/> by C-four plants <pause dur="0.9"/> <vocal desc="cough" iterated="n" n="ss" dur="1"/> <pause dur="1.9"/> in theory anyway so individual leaves <pause dur="0.5"/> # <pause dur="0.4"/> if we're talking about <pause dur="1.6"/> # almost a doubling of C-O-two concentration <pause dur="0.2"/> by the end of the century <pause dur="0.5"/> that will give something like a fifty per cent <pause dur="0.3"/> increase in the rate of photosynthesis of individual of individual leaves <pause dur="0.6"/> # <pause dur="0.7"/> there there might be a small effect on C-four species i mean the the <pause dur="0.7"/> the evidence is a bit divided <pause dur="0.3"/> some people say there's no effect some people might be small effect <pause dur="0.4"/> but it's certainly going to be less than ten per cent <pause dur="0.8"/> # <pause dur="0.3"/> so that seams good that <pause dur="0.6"/> that's a positive effect of climatic change in a way that that <pause dur="0.5"/>

going to have increase rates of photosynthesis <pause dur="0.7"/> which <pause dur="0.4"/> again is a way of increasing the storage of carbon on the land's surface if we if we keep <unclear> as both </unclear> <pause dur="0.9"/> # <pause dur="0.2"/> but it's not quite as straight forward as as that <pause dur="0.6"/> # <pause dur="1.3"/> one thing that <pause dur="0.4"/> generally will happen <pause dur="0.4"/> is that <kinesic desc="indicates board on wall" iterated="n"/> <pause dur="0.6"/> most evidence seems to be that <kinesic desc="indicates board on wall" iterated="n"/> there's going to be an increase in stomatal resistance <pause dur="1.2"/> if C-O-two concentration increases plants tend to close their stomata a little bit <pause dur="0.4"/> # <pause dur="0.6"/> they don't need to have them so wide open for photosynthesis <pause dur="0.6"/> # <pause dur="0.9"/> now that's <pause dur="0.9"/> that's good in some ways because it'll <kinesic desc="indicates board on wall" iterated="n"/> probably reduce transpiration <pause dur="0.7"/> # <pause dur="0.5"/> reduce the rate of water loss <pause dur="0.4"/> so we'll get more dry matter produced per unit of water used <pause dur="0.5"/> # <pause dur="0.2"/> it's been called water use efficiency <pause dur="0.7"/> # <pause dur="0.3"/> we've mentioned before the the ration of of dry matter to to water use

<pause dur="0.7"/> # <pause dur="1.5"/> so that's sort of positive <pause dur="0.3"/> # <pause dur="0.3"/> but the stomata resistance may feed back and sort of cut down on this fifty per cent <pause dur="0.6"/> increase so you may get less less increase than that <pause dur="1.3"/> # <pause dur="1.2"/> but think back earlier on in the course we looked at the energy balance of leaves <pause dur="0.7"/> and <pause dur="0.7"/> and of crops <pause dur="0.4"/> and the energy got to go somewhere and if you reduce the transpiration <pause dur="0.5"/> then you're probably going to have an increase in in leaf temperature <pause dur="0.2"/> and # <pause dur="0.2"/> that may feed back into local air temperatures <pause dur="0.5"/> but <pause dur="1.0"/> when <kinesic desc="indicates board on wall" iterated="n"/> the warmer leaf temperature have <pause dur="1.2"/> a positive or negative effect on the leaf <pause dur="0.2"/> photosynthesis again is not really clear <pause dur="0.3"/> # it may be that there may be a negative effect of of warmer temperatures <pause dur="0.6"/> # <pause dur="0.7"/> so <pause dur="1.0"/> basically <pause dur="0.5"/> positive in C-three species but not necessarily that that clear <kinesic desc="changes powerpoint slide" iterated="n"/> <pause dur="2.8"/> now when you come <trunc> t </trunc> <pause dur="0.5"/>

that really i'm talking about individual leaf you know an individual leaf exposed to different levels of carbon dioxide <pause dur="0.7"/> but <pause dur="0.8"/>when you come to a crop the effects are likely to be less than for a crop the individual leaf <pause dur="0.5"/> because not all the leaves as we talked before we looked at light not all the leaves are <pause dur="0.8"/> receiving the same level of light <pause dur="0.5"/> the old leaves at the bottom probably won't respond to <pause dur="0.9"/> to C-O-two et cetera <pause dur="0.4"/> # <pause dur="0.3"/> so <pause dur="0.3"/> most values show the <pause dur="0.5"/> effects are less <pause dur="0.7"/> for a crop than for an individual leaf <pause dur="4.3"/> but also leaves may actually sort of acclimatize <pause dur="0.5"/> to the changing in C-O-two level <pause dur="0.5"/> # <pause dur="0.5"/> those results i put up before are really sort of <unclear> in </unclear> experiments i think we're probably using measure photosynthesis <pause dur="0.8"/> # <pause dur="0.9"/> and it may be <pause dur="0.4"/> that plants adapt to the to the rates to the levels of C-O-two and reduce their rates over time <pause dur="1.0"/> there's a sort of <pause dur="0.2"/> <trunc> s </trunc>

<pause dur="0.4"/> phrase that's used here about down-regulating that plants control their rate of metabolism <pause dur="0.8"/> # <pause dur="0.9"/> so <pause dur="0.3"/> there's been a lot of interest recently in actually looking at long term studies <pause dur="0.4"/> # <pause dur="0.2"/> of the effects of C-O-two <pause dur="0.5"/> changes <pause dur="0.7"/> if you expose plants to different levels of C-O-two for a long time <pause dur="0.2"/> do they change their photosynthesis <pause dur="1.0"/> # <pause dur="1.0"/> and of course plant growth is not just <pause dur="2.0"/> determined by carbon dioxide <pause dur="0.2"/> you've got other interactions particularly with water nutrients and temperature <pause dur="0.4"/> so <pause dur="0.3"/> what i'm going to do now is tell you bit about some longer term studies that've been going on looking at looking at these things <pause dur="1.0"/> # <pause dur="1.2"/> i don't know have you ever come across the term FACE at all anybody not in in this context <pause dur="0.5"/> # <pause dur="0.7"/> well it stand for free air C-O-two enrichment <pause dur="0.5"/> # <pause dur="1.2"/> basically <pause dur="1.2"/> if you think about <pause dur="0.3"/> what how do you experiments about C-O-two <pause dur="0.3"/> you could

<pause dur="0.9"/> do experiments in the glass house # you could increase the C-O-two level in the glass house and look at the response <pause dur="1.0"/> as is done in <pause dur="0.2"/> commercial tomato production for <trunc> ex </trunc> example <pause dur="0.5"/> getting increased growth rates <pause dur="0.5"/> # <pause dur="0.4"/> but what what we really don't know is what's gong to happen to plants <pause dur="0.6"/> in the atmosphere outside <pause dur="0.6"/> so the idea of of these sort of experiments which are <pause dur="0.3"/> quite complicated <unclear> only done </unclear> in a few places in the world <pause dur="0.4"/> is <kinesic desc="indicates board on wall" iterated="n"/> <pause dur="0.8"/> to actually have <pause dur="0.4"/> experiments outside <pause dur="0.3"/> where <pause dur="1.0"/> # <pause dur="0.4"/> C-O-two enriched air is released over vegetation and continuously released <pause dur="0.2"/> so you've got plants or trees and things growing <pause dur="0.6"/> in <pause dur="0.8"/> increased C-O-two levels outside in real conditions <pause dur="0.7"/> # <pause dur="1.1"/> so there's a lot of sort of engineering going on to control the carbon dioxide <pause dur="0.5"/> # <pause dur="0.7"/> levels <pause dur="1.0"/> # and provide a stable elevated level of carbon dioxide <pause dur="1.8"/> and <pause dur="0.4"/>

basically there should be no barrier to natural air flow so the wind et cetera can have its normal effect so the <unclear> issue </unclear> is not not affecting not affected <pause dur="0.7"/> # <pause dur="1.0"/> and <pause dur="1.6"/> basically <pause dur="0.3"/> these facilities have been built up mainly in in the states though there's been some work in the U-K <pause dur="0.3"/> # on a on a slightly smaller scale <pause dur="0.4"/> # but these ones are going to be <pause dur="0.5"/> # <pause dur="0.8"/> ones i'm going to show you in America <pause dur="0.7"/> # <pause dur="1.4"/> this is basically saying if we can't use full scale changes we need to use <pause dur="0.4"/> # <pause dur="0.4"/> bigger systems to look at <pause dur="0.2"/> but don't <kinesic desc="indicates board on wall" iterated="n"/> change the micro climate <pause dur="0.5"/> very much <pause dur="0.7"/> # <pause dur="0.8"/> so <pause dur="0.3"/> lets have a look this is this is a <pause dur="0.4"/> # <pause dur="1.0"/> called a FACE facility <pause dur="0.4"/> in <pause dur="0.5"/> # North Carolina <pause dur="0.5"/> # <pause dur="0.2"/> and these are <pause dur="0.4"/> the the facilities and these are circles about thirty metres <pause dur="0.6"/>

wide <pause dur="0.5"/> # <pause dur="0.5"/> and these are just vertical pipes around here which <pause dur="0.2"/> let C-O-two in <pause dur="0.6"/> across the vegetation inside there <pause dur="0.6"/> # now obviously you've got to have different treatments and things so it all gets a bit complicated <pause dur="0.4"/> # <pause dur="0.7"/> building up <pause dur="0.4"/> # those sort of facilities <pause dur="0.3"/> # so they're quite a major investment <pause dur="0.7"/> # <pause dur="0.4"/> but these have been going <pause dur="0.7"/> in the states for <pause dur="0.2"/> # <pause dur="0.2"/> since the sort of <trunc> mid-nineteen-sev </trunc> # mid-nineteen-nineties <pause dur="0.3"/> and built up some some useful results <pause dur="1.1"/> # <pause dur="2.4"/> so <pause dur="0.6"/> # <pause dur="0.5"/> <trunc> th </trunc> these are some results <trunc> fr </trunc> from that particular one looking at # <pause dur="0.8"/> # <pause dur="1.0"/> it's pine forest <pause dur="0.3"/> # <pause dur="0.7"/> in in U-S-A <pause dur="0.5"/> and <pause dur="1.1"/> you've got a control plot <pause dur="0.5"/> where <pause dur="0.3"/> the <pause dur="0.2"/> normal <pause dur="0.4"/> ambient C-O-two level <pause dur="0.2"/> three-sixty-five parts per million roughly <pause dur="0.5"/>

# <pause dur="0.2"/> and they <pause dur="0.3"/> increased that by two-hundred so the <pause dur="0.2"/> the treatment there is is two-hundred parts per million <pause dur="1.0"/> i'm sorry two-hundred parts per million extra <pause dur="0.3"/> five-sixty five-sixty-five parts per million <pause dur="0.6"/> # <pause dur="0.2"/> so that's <pause dur="0.3"/> experiment <pause dur="0.3"/> # <pause dur="0.8"/> is still running but they've only actually got the results up until two-thousand sort of published so far <pause dur="0.4"/> and <pause dur="1.0"/> do you remember back in <pause dur="0.2"/> one of the earlier works we talked about net primary production N-P-P <pause dur="0.8"/> how much production as a forest or something will produce <pause dur="0.6"/> over a year <pause dur="0.6"/> so <pause dur="0.2"/> this is what these figures are grammes per metre squared per year <pause dur="0.8"/> # <pause dur="0.7"/> and <pause dur="0.5"/> basically there's variation from year to year # <pause dur="0.3"/> natural other factors water rainfall <pause dur="0.7"/> solar radiation temperature et cetera <pause dur="0.5"/> but as you can see <pause dur="0.2"/> in each year

so far <pause dur="0.6"/> # <pause dur="2.1"/> the the trees receiving the higher level of C-O-two have produced <pause dur="0.2"/> more more <pause dur="0.4"/> biomass <pause dur="0.4"/> # <pause dur="0.4"/> somewhere between twenty and thirty per cent <pause dur="1.1"/> # <pause dur="0.4"/> more increase <pause dur="0.6"/> # <pause dur="0.7"/> and then this supports the fact that <pause dur="0.8"/> over time <pause dur="0.5"/> as the C-O-two concentration in the atmosphere has gone up historically <pause dur="0.3"/> then <pause dur="0.9"/> certainly suggests that this <pause dur="0.5"/> this type of forest will have been accumulating <pause dur="0.4"/> biomass at a at a bigger rate <pause dur="0.5"/> we talked about <pause dur="0.3"/> over the last <pause dur="0.7"/> twenty years how we think that the net the earth's surface the the vegetation of the earth's surface has been a net

<pause dur="0.8"/> sink for C-O-two taking up C-O-two so this is part of the story <kinesic desc="indicates board on wall" iterated="n"/> <pause dur="1.2"/> plants responding to to C-O-two concentration <pause dur="1.8"/> does that seem okay at the moment is that <pause dur="1.7"/> # <pause dur="0.9"/> okay we'll go a bit further on those results then <pause dur="0.3"/> # <pause dur="2.0"/> so <pause dur="0.3"/> you <pause dur="0.3"/> so far there's been an increase in dry matter in a fraction over four years <pause dur="0.5"/> # <pause dur="0.7"/> but the sort of papers and that suggest that <pause dur="1.6"/> this may well <trunc> c </trunc> carry on <pause dur="0.4"/> but <pause dur="0.4"/> may not be sustained if nitrogen <pause dur="0.5"/> becomes limited obviously <pause dur="0.5"/> nitrogen is involved in in growth processes <pause dur="0.5"/> and <pause dur="1.1"/> can't necessarily <pause dur="0.2"/> # <pause dur="1.5"/> sustain increased rates of C-O-two if <pause dur="0.6"/> you don't add any more nitrogen <pause dur="0.4"/> # either naturally or not now there's again <pause dur="0.2"/> concern in <pause dur="0.4"/> that we're increasing the global nitrogen cycle <pause dur="0.2"/> so maybe <pause dur="0.2"/> that's happening anyway <pause dur="0.3"/> # <pause dur="1.0"/> and there's need for measurements of nitrogen then but at the moment it does seem to be sustained and carried on <pause dur="0.7"/> #

<pause dur="1.1"/> so there's <pause dur="0.5"/> # no evidence here of of acclimatization of of plants down regulating the photosynthesis <pause dur="1.0"/> # <pause dur="0.3"/> there's also <pause dur="0.5"/> over those four years no matter no difference in dry matter partitioning <pause dur="1.1"/> the increased dry matter's going to leaves <pause dur="0.3"/> roots <pause dur="1.0"/> trunks et cetera in the same proportions as it was before <pause dur="0.6"/> # <pause dur="1.5"/> so you're just getting bigger trees but they're in the same proportions <pause dur="0.9"/> # <pause dur="1.7"/> there's also <kinesic desc="indicates board on wall" iterated="n"/> <trunc> s </trunc> no difference in stomatal resistance or or water use they've also measured those <pause dur="0.2"/> things there <pause dur="0.3"/> so basically these trees are producing more dry matter <pause dur="0.5"/> # for the same amount of water so they've got a greater water use efficiency <pause dur="0.9"/> # <pause dur="1.2"/> so <pause dur="0.2"/> this seems a fairly straightforward <pause dur="0.3"/> response it's <pause dur="0.7"/> it's behaving almost in expects <pause dur="0.2"/> as you'd expect it to <pause dur="0.2"/> # <pause dur="0.4"/> for simple rates of photosynthesis <pause dur="4.0"/> # <pause dur="4.2"/> <trunc> a </trunc> again in these experiments they measure all sorts of things <pause dur="0.4"/> and <pause dur="1.0"/> if you remember back # in about week five <pause dur="0.3"/> we # said that one way of analysing

crop growth <pause dur="0.7"/> was to think about <pause dur="0.2"/> <kinesic desc="indicates board on wall using a stick" iterated="n"/> the dry matter produced grammes per meter squared <pause dur="0.8"/> in this case per year <pause dur="0.5"/> # <pause dur="0.7"/> as being made up of two things the absorbed <pause dur="1.0"/> radiation the the <pause dur="0.6"/> crop <pause dur="0.2"/> or the trees in this case captured in the sun <pause dur="0.5"/> # <pause dur="0.2"/> and <pause dur="0.7"/> the # <pause dur="1.1"/> thing called the radiation <unclear> sufficiency </unclear> <pause dur="0.2"/> which <pause dur="0.2"/> was basically <pause dur="0.2"/> how you turn the absorbed radiation in in into into dry matter <pause dur="0.8"/> # <pause dur="0.6"/> how many grammes of dry matter you get per mega joule of radiation absorbed <pause dur="0.2"/> # <pause dur="1.1"/> what these <trunc> a </trunc> are <pause dur="0.2"/> data from <pause dur="0.8"/> from <trunc> th </trunc> <pause dur="0.5"/> those trees <pause dur="0.2"/> # <pause dur="1.8"/> and <pause dur="0.5"/> essentially this bottom one is # three-sixty-five parts per million the normal <pause dur="0.2"/> <trunc> environm </trunc> the normal environment <pause dur="0.6"/> # <pause dur="0.3"/> <kinesic desc="indicates board on wall using a stick" iterated="n"/> and the five-sixty-five one here <pause dur="0.3"/> and you can see that <pause dur="0.3"/> over time there's really been no difference in the amount of radiation intercepted <pause dur="0.2"/> that's still <pause dur="1.1"/> still constant <pause dur="0.6"/> #

<pause dur="1.0"/> they're trees that've got a reasonable leaf area they they've got a leave area <unclear> in </unclear> about three to four <pause dur="0.2"/> so they're capturing a reasonable amount of light <pause dur="0.6"/> # <pause dur="0.4"/> and there's no difference here <kinesic desc="indicates board on wall using a stick" iterated="n"/> the difference is in <pause dur="0.2"/> the radiation sufficiency <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.5"/> # which is what you'd expect really that's the <pause dur="1.8"/> that's the photosynthetic processes the conversion of <trunc> radi </trunc> # radiant energy into dry matter <pause dur="0.4"/> # that's been increased by by photosynthesis <pause dur="0.7"/> # <pause dur="0.2"/> so that's one example of of how the radiation <unclear> we used to understand the experiment </unclear> <pause dur="2.2"/> is that <pause dur="0.4"/> okay so far <pause dur="2.7"/> okay # so that's <pause dur="0.8"/> one bit <pause dur="0.4"/> # <pause dur="1.3"/> another <pause dur="1.0"/> FACE facility is in the University of Arizona <pause dur="0.5"/> # <pause dur="0.3"/> where they did experiments on wheat <pause dur="0.6"/> # <pause dur="0.4"/> so again <pause dur="0.5"/> these circles <kinesic desc="indicates board on wall using a stick" iterated="n"/> with C-O-two enrichment <pause dur="0.5"/> # <pause dur="0.3"/> coming in <kinesic desc="indicates board on wall" iterated="n"/> across the <pause dur="0.6"/> the individual plots in there <pause dur="0.5"/> # <pause dur="0.6"/> again a reasonable distance between the plots <pause dur="0.2"/> so avoids cross contamination and things like that <pause dur="0.4"/> # <pause dur="1.5"/> what do they <pause dur="0.4"/> show for wheat <pause dur="0.7"/> well <pause dur="0.7"/> that's a bit

more complicated really <pause dur="0.5"/> # <pause dur="1.0"/> they had # used a fifty per cent increase in carbon dioxide <pause dur="0.4"/> so you have <pause dur="0.5"/> plants at normal # <pause dur="0.6"/> atmospheric carbon dioxide and ones with fifty per cent increase <pause dur="0.8"/> # <pause dur="1.1"/> and <pause dur="0.4"/> there was a strong interaction between <pause dur="0.3"/> carbon dioxide and water use <pause dur="1.0"/> # <pause dur="2.2"/> the water use was reduced <pause dur="0.4"/> by about six per cent <pause dur="2.0"/> from well watered crops so there was there was some <pause dur="0.7"/> reduction in in stomatal resistance <pause dur="0.7"/> # stomatal stomata were probably closing a little bit <pause dur="0.8"/> # <pause dur="1.5"/> but <pause dur="1.5"/> in terms of the photosynthesis <pause dur="0.4"/> # <pause dur="1.0"/> when you had crops <pause dur="0.5"/> with <pause dur="0.3"/> adequate water <pause dur="0.7"/> well watered crops <pause dur="0.2"/> you got something like about a nineteen per cent increase <pause dur="0.5"/> # <pause dur="0.5"/> in in in photosynthesis <pause dur="0.5"/> for for the canopy <pause dur="0.5"/> # <pause dur="0.5"/> now you might expect on an individual leaf something like thirty per cent <pause dur="0.4"/> but it <pause dur="0.2"/> as i said earlier it's probably less for an individual <pause dur="0.4"/> for a for a whole crop <pause dur="0.6"/> so <pause dur="2.1"/> wheat # C-three species getting an increase in in canopy photosynthesis <pause dur="0.6"/> <kinesic desc="indicates board on wall" iterated="n"/> from C-O-two <pause dur="0.6"/> # <pause dur="0.3"/> but actually doing better

<kinesic desc="indicates board on wall" iterated="n"/> <pause dur="0.9"/> when you've got water deficiency <pause dur="0.6"/> # <pause dur="0.9"/> that <pause dur="1.4"/> when the crop is short of water the # the <pause dur="1.0"/> increase in C-O-two <unclear> is able to </unclear> compensate for that <pause dur="0.3"/> and and <pause dur="0.2"/> boost up rates of photosynthesis <pause dur="0.8"/> # <pause dur="0.6"/> so <pause dur="0.2"/> you've got a much greater increase <trunc> un </trunc> under water stress <pause dur="0.8"/> # <pause dur="1.4"/> so <pause dur="1.0"/> thus suggests that plants may <pause dur="0.4"/> the combination of <pause dur="0.7"/> # <pause dur="0.5"/> high C-O-two <trunc> an </trunc> and <pause dur="0.2"/> reduced water <pause dur="0.2"/> might be <pause dur="0.6"/> there might be some compensation there but it certainly in in wheat <pause dur="0.7"/> # <pause dur="1.2"/> but obviously when you come on to future predictions of what's happening to crops <pause dur="0.7"/> what's going to happen about # <pause dur="0.6"/> water <pause dur="0.7"/> # <pause dur="0.4"/> around the world is is very important <pause dur="4.0"/> # <pause dur="1.4"/> okay so that's looked at C-O-two <pause dur="0.4"/> # <pause dur="0.7"/> and some interactions with water <pause dur="0.5"/> but <pause dur="1.5"/> in the <pause dur="0.2"/> in what we think's going to be the world in the next next century <pause dur="0.5"/> # <pause dur="0.4"/> any increases in carbon dioxide are going to be <pause dur="0.4"/> accompanied by increases in

temperature <pause dur="0.7"/> # <pause dur="0.5"/> generally on average <pause dur="0.3"/> # <pause dur="1.1"/> you know we talked about mean temperatures increase increasing but in general there's going to be increase in temperature <pause dur="0.4"/> so <pause dur="0.4"/> we need to think about that those interactions <pause dur="0.7"/> # <pause dur="1.1"/> and <pause dur="0.8"/> we remember we struggled a bit with thermal time earlier on this product of temperature and time <pause dur="0.5"/> which really controls the development of crops <pause dur="1.0"/> so <pause dur="0.4"/> warmer temperatures mean quicker development <pause dur="0.9"/> # <pause dur="0.2"/> so <pause dur="0.6"/> present day varieties will <pause dur="0.2"/> mature quicker <pause dur="0.6"/> and have less time for photosynthesis <pause dur="0.5"/> # <pause dur="0.3"/> do you remember we did the thing about maize and altitude in in one one of the <pause dur="0.4"/> lectures there <pause dur="0.3"/> # <pause dur="0.8"/> so <pause dur="0.4"/> what's going to happen <pause dur="0.3"/> # <pause dur="1.9"/> # <pause dur="0.8"/> when <pause dur="0.8"/> when temperatures increase <pause dur="0.4"/> # in combination with C-O-two levels <pause dur="0.6"/> well there've only been experiments <pause dur="1.2"/> on wheat <pause dur="0.4"/> there were some done here actually in <gap reason ="name" extent="1 word"/> <pause dur="0.2"/> and at Rothamsted experimental station <pause dur="0.4"/> # <pause dur="1.1"/> the ones here they they grew plants in plastic tunnels <pause dur="0.5"/> with big heaters at one end <pause dur="0.3"/> # increased the C-O-two level and got a grade of temperature went down the tunnel so you could look at the effects of temperature and C-O-two concentration <pause dur="0.5"/> and basically <pause dur="0.7"/> in terms of <pause dur="0.8"/> yield and things <pause dur="0.9"/> increases due to carbon dioxide <pause dur="0.3"/> were cancelled out <pause dur="0.4"/> or <pause dur="0.2"/> doubling of carbon dioxide <pause dur="0.5"/> <kinesic desc="indicates board on wall" iterated="n"/> was cancelled out by about a two degree temperature increase <pause dur="0.3"/> # <pause dur="0.4"/> because # <pause dur="0.4"/> the temperature increase meant the the plant growth was ever quicker <pause dur="1.2"/> # <pause dur="1.4"/> and this was sort of illustrated by <pause dur="1.0"/> sort of crop modelling if you like <pause dur="0.6"/> # <pause dur="0.2"/> i mean crop models are basically trying to <pause dur="0.2"/> people trying to predict how crops grow <pause dur="0.4"/> and they're based on things like thermal time and radiation efficiency <pause dur="0.6"/> # <pause dur="0.5"/> and <pause dur="1.5"/> these are some of the results

they expect for a wheat crop <pause dur="0.3"/> this <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.2"/> crop labelled nineteen-eighty-one refers to <pause dur="0.5"/> typical conditions <trunc> a </trunc> <pause dur="0.5"/> in in the nineteen-eighties <pause dur="0.5"/> so that <kinesic desc="indicates board on wall using a stick" iterated="n"/> might be total dry matter <pause dur="0.3"/> of a wheat crop <pause dur="0.8"/> # <pause dur="0.5"/> over time giving you something like <pause dur="0.8"/> # <kinesic desc="indicates board on wall using a stick" iterated="n"/> twenty tons per hectare so it's a pretty good crop <pause dur="1.6"/> then bringing those sort of results we've got in <pause dur="0.4"/> if you double carbon dioxide <pause dur="0.7"/> # <pause dur="0.2"/> you get a higher rate of photosynthesis and get more dry matter <pause dur="1.0"/> # <pause dur="0.6"/> so that's a doubling of carbon dioxide <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="2.1"/> but <pause dur="0.2"/> you also <kinesic desc="indicates board on wall using a stick" iterated="n"/> accelerate if you if you then <kinesic desc="indicates board on wall using a stick" iterated="n"/> have a three degree increase in temperature <pause dur="0.8"/> # you accelerate

development so you get the dry matter <pause dur="0.7"/> # and you get it quicker that that all seems fine you getting more dry weight and <trunc> an </trunc> in a quicker <pause dur="0.8"/> in a quicker time <pause dur="0.7"/> # <pause dur="0.6"/> but that then leaves little time <pause dur="1.0"/> for the grain <pause dur="0.6"/> to fill <pause dur="0.5"/> # <pause dur="0.2"/> in terms of grain weight <pause dur="0.6"/> # <pause dur="1.5"/> basically what you tend to happen is you accelerate the grain filling process <pause dur="0.6"/> and you don't get a lot enough time to fill grain so <pause dur="0.3"/> in terms of grain yield you get relatively difference <pause dur="0.8"/> between the conditions here and the conditions there <pause dur="0.5"/> # <pause dur="0.6"/> so this rapid development <pause dur="0.4"/> of of of cereal crops <pause dur="0.3"/> # sort of cancels out <pause dur="0.7"/> # <pause dur="0.3"/> the # <pause dur="1.2"/> the effect of <trunc> s </trunc> carbon dioxide <pause dur="0.2"/> and you don't get much effect upon upon yield <pause dur="0.8"/> does that seem to make any sense to people or not <pause dur="4.9"/> maybe <pause dur="0.5"/> ok <pause dur="0.5"/> # <pause dur="4.0"/> what what about other crops <pause dur="0.2"/> # <pause dur="1.0"/> well <pause dur="0.2"/> things like # <pause dur="0.6"/> vegetative crops <pause dur="0.7"/> # <pause dur="0.8"/> things like sugar beet and potatoes where you're not actually growing them for seed for grain <pause dur="0.7"/> # <pause dur="0.6"/> they're not so <pause dur="0.2"/> restricted by developments they will <pause dur="2.2"/> have yield formation over a longer period <pause dur="0.3"/> # <pause dur="0.3"/> continue growth along that <pause dur="0.2"/>

so <pause dur="0.8"/> basically the effects of carbon dioxide doubling there tend to be <pause dur="0.5"/> greater than the effects of negative effects of temperature <pause dur="0.3"/> # <pause dur="0.4"/> so provided you've got water you tend to <pause dur="0.3"/> evidence seems to be that you'll get an increasing yield <pause dur="0.9"/> on on those sort of crops <pause dur="7.5"/> okay so <pause dur="2.1"/> we're starting to get together a picture of how carbon dioxide <pause dur="0.6"/> and <pause dur="0.3"/> temperature <pause dur="0.5"/> # <trunc> inter </trunc> influence <pause dur="0.3"/> yields of crops <pause dur="1.0"/> one thing that's going to <pause dur="0.4"/> obviously differ <pause dur="0.3"/> in in climatic change is <pause dur="0.3"/> distribution of crops <pause dur="0.7"/> # <pause dur="0.9"/> it's slightly <gap reason="inaudible due to noise from audience" extent ="0.4 sec"/> illustrates the point quite quite nicely <pause dur="0.4"/> # <pause dur="0.7"/> this is maize in the U-K <pause dur="0.3"/> # <pause dur="1.0"/> now we don't really grow <pause dur="0.2"/> maize for grain <pause dur="0.6"/> # <pause dur="0.5"/> like they do in France <pause dur="0.7"/> grain for feeding of animals where you actually <pause dur="0.3"/> harvest the mature grain <pause dur="0.7"/> # because basically the season's really too too short <pause dur="0.6"/> # <pause dur="2.4"/> well we grow the maize for silage where we harvest the whole the whole crop <pause dur="0.4"/> and obviously we grow things for sweetcorn but sweetcorn's not mature grain it's an in between <pause dur="0.4"/> and <pause dur="0.5"/> # <pause dur="1.3"/> <vocal desc="cough" iterated="y" n="ss" dur="1"/> around the <pause dur="0.2"/> the end of <pause dur="0.4"/> well eighteen nineteen-eighty-seven nineteen-ninety <pause dur="0.4"/> # <pause dur="0.7"/> in terms of temperature <pause dur="0.7"/> the limit for grain maize is pretty well the south coast it can be grown in in <trunc> Fr </trunc> in <pause dur="0.3"/> northern France but not so much in the U-K

<pause dur="0.7"/> # <pause dur="0.9"/> an increase of <pause dur="0.2"/> half a degree in mean temperature <pause dur="0.5"/> would put the limit up to here <kinesic desc="indicates board on wall" iterated="n"/> <pause dur="0.2"/> one-and-a-half here <kinesic desc="indicates board on wall" iterated="n"/> and three degrees would take it up in into Scotland <pause dur="0.6"/> because temperature's the limiting factor <pause dur="0.6"/> based upon this thermal time <pause dur="0.8"/> # <pause dur="0.4"/> silage maize <pause dur="0.8"/> <kinesic desc="indicates board on wall using a stick" iterated="n"/> limit there <pause dur="0.5"/> # <pause dur="2.3"/> could could move quite appreciably <pause dur="0.5"/> # <pause dur="2.0"/> the other point about here <kinesic desc="indicates board on wall using a stick" iterated="n"/> is <pause dur="0.3"/> on here <kinesic desc="indicates board on wall using a stick" iterated="n"/> are some particularly <pause dur="0.4"/> # <pause dur="1.3"/> nineteen-seventy-six was a particularly hot year <pause dur="0.4"/> and <pause dur="0.3"/> before we got into <pause dur="1.0"/> the late nineteen-nineties and the warmest years of the millennium <pause dur="0.4"/> # <pause dur="0.3"/> and in that year the limit stop up here already <pause dur="0.3"/> a cold year <kinesic desc="indicates board on wall using a stick" iterated="n"/> nineteen-sixty-two it was down here <pause dur="0.4"/> so <pause dur="2.3"/> we've already experienced individual years some of the fluctuations of the same sort of size <pause dur="0.5"/> # as things that we're we're getting <pause dur="0.7"/> # <pause dur="0.7"/> but <pause dur="0.3"/> basically <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="3.0"/> even a sort of one or two degree <pause dur="0.8"/> limit a change in temperature <pause dur="0.3"/> will vastly increase the range in which various crops can be grown going to be a lot of changes <pause dur="0.3"/> in in in crop composition <pause dur="0.7"/> and and and <unclear> into </unclear> grow in different places <pause dur="3.3"/> # <pause dur="2.7"/> what sort of yields could you get for for maize and i've put this in to illustrate one particular point <pause dur="0.5"/> # <pause dur="0.3"/> that <pause dur="0.7"/> these are estimated yields of forage maize <pause dur="0.5"/> in the U-K <pause dur="0.6"/> #

<pause dur="0.5"/> and basically <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.3"/> the darker areas are the <pause dur="1.1"/> highest yielding areas at the moment <pause dur="0.9"/> # you can't get any yield of maize <pause dur="0.6"/> and <pause dur="0.3"/> this study looked at <pause dur="0.7"/> what would you what would happen to maize yields <pause dur="0.2"/> if <pause dur="0.3"/> i'm sorry it's off the top of the screen here but <pause dur="0.2"/> it's increase temperature by two degrees <pause dur="0.6"/> and rainfall by <pause dur="0.2"/> ten per cent <pause dur="1.0"/> # <pause dur="0.7"/> very simple <pause dur="0.8"/> # <pause dur="1.0"/> adjustment in in <pause dur="0.4"/> # <pause dur="0.7"/> in climate <pause dur="0.3"/> <unclear> do you see </unclear> that the mean temperature's gone up by two degrees and rainfall's increased by ten per cent <pause dur="0.2"/> there's no effect of carbon dioxide in here <pause dur="0.4"/> and <pause dur="0.6"/> # <pause dur="1.4"/> the yields <kinesic desc="indicates board on wall using a stick" iterated="n"/> basically increase <pause dur="0.4"/> # <pause dur="0.2"/> and particularly increase <pause dur="0.8"/> <kinesic desc="indicates board on wall using a stick" iterated="n"/> in in the midlands and the west of of the country <pause dur="2.5"/> but <pause dur="0.4"/> if you increase

temperatures by two degrees <pause dur="1.0"/> but decrease rainfall by ten per cent <pause dur="1.4"/> you get a lot of these lighter colours <pause dur="0.4"/> # <pause dur="0.3"/> and the the increase yield is <pause dur="0.6"/> is # <pause dur="0.4"/> disappeared <pause dur="1.0"/> and this is one of the great uncertainties really <pause dur="0.2"/> is that <pause dur="1.8"/> we not really sure what's going to happen to rainfall in in in <pause dur="2.0"/> the <pause dur="0.4"/> in the coming centuries <pause dur="0.4"/> and <pause dur="0.3"/> things like maize et cetera are very sensitive <pause dur="0.2"/> to to to rainfall <pause dur="0.5"/> plus or minus ten per cent <pause dur="0.5"/> there's almost nothing you get a complete change of yield pattern <pause dur="0.5"/> # <pause dur="0.2"/> between those two conditions <pause dur="0.4"/> so <pause dur="1.2"/> got to be very careful about what you read and believe because <pause dur="2.1"/> knowing what the future rainfall is going to be is very important in terms of <pause dur="0.6"/> # not only agricultural crops but in terms of natural vegetation as well <pause dur="2.5"/> # <pause dur="2.2"/> okay <pause dur="0.9"/> some sources of information <pause dur="0.2"/> about # <pause dur="1.0"/> climatic change and impacts <pause dur="0.3"/> and i've stuck this one in here <pause dur="0.2"/> # <pause dur="1.3"/>

U-K <pause dur="0.4"/> C-I-P United Kingdom <pause dur="0.3"/> # <pause dur="1.6"/> climate impacts programme <pause dur="0.4"/> # it's it's quite a substantial <pause dur="0.4"/> activity <pause dur="0.3"/> # <pause dur="1.7"/> funded by DEFRA <pause dur="0.6"/> # based really at the university of Oxford <pause dur="0.3"/> # <pause dur="0.3"/> provide a lot of information on put up the website a <trunc> b </trunc> a bit later on <pause dur="0.9"/> # <pause dur="1.4"/> one of the things they did # and i put this in really for those of interest in some ways but it is interesting <pause dur="0.5"/> # they commissioned <pause dur="0.6"/> a report on <pause dur="0.3"/> on what's going to happen to gardens in the next <pause dur="0.3"/> millennium <pause dur="0.6"/> # sorry the next hundred years # not only domestic gardens but also <pause dur="0.3"/> # <pause dur="0.5"/> you know stately homes and things like that <pause dur="0.3"/> and # <pause dur="1.9"/> <gap reason ="name" extent="1 word"/> had <gap reason="inaudible" extent ="0.4 sec"/> grow here so who're responsible for this this report <pause dur="0.6"/> # <pause dur="0.8"/> and <pause dur="0.2"/> produced a few <pause dur="1.4"/> fairly <pause dur="0.2"/> what i think fairly interesting figures some of us're looking back at the climatic records <pause dur="0.6"/> # <pause dur="1.1"/> this is the central England's temperature record <pause dur="0.8"/> # <pause dur="0.9"/> which we said before # it goes back to about seventeen-seventy <pause dur="0.6"/> # <pause dur="0.5"/> and <pause dur="0.5"/> these are the number of hot days <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.5"/> # <pause dur="0.4"/> days above <pause dur="0.4"/> twenty degrees in a year <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.6"/> # <pause dur="1.4"/> and <pause dur="0.2"/> you can see <kinesic desc="indicates board on wall using a stick" iterated="n"/> that

there's # a general <pause dur="0.4"/> general increase trend this is <kinesic desc="indicates board on wall using a stick" iterated="n"/> like a smooth curve <pause dur="1.9"/> going through here and the colour's just to highlight the areas above and below <pause dur="0.4"/> # <pause dur="0.2"/> this is the nineteen <pause dur="0.3"/> # sixty-one to ninety average <pause dur="0.8"/> # <pause dur="0.4"/> so <pause dur="0.3"/> over the last few years the number of hot days has increased <pause dur="0.7"/> # <pause dur="0.7"/> and <pause dur="0.8"/> these are the number of of cold days <pause dur="0.4"/> # <pause dur="1.9"/> # <pause dur="4.2"/> linked in to frost occurrence we saw this before but certainly that occurrence is is is much less <pause dur="0.3"/> in the last part of this century than than back in the previous centuries <pause dur="0.6"/> and and those are <pause dur="0.2"/> things that are relevant to to to garden plants <pause dur="2.0"/> the length of the growing season <pause dur="0.4"/> # <pause dur="0.9"/> we talked back in earlier times about <pause dur="0.6"/> thermal time <pause dur="0.6"/> and <pause dur="0.4"/> roughly <pause dur="0.4"/> # <pause dur="2.5"/> growing season is is roughly defined for time when temperature <pause dur="0.4"/> is above <pause dur="0.6"/> # <pause dur="0.2"/> is is greater than five degrees <kinesic desc="writes on board" iterated="y" dur="1"/> five degrees <pause dur="0.8"/> five degrees centigrade roughly speaking <pause dur="0.5"/> so this is the number of days in in a year in central England <pause dur="0.6"/> # <pause dur="0.4"/> that the the growing season has been <pause dur="0.7"/> # the temperatures have been above five degrees <pause dur="0.4"/> # <pause dur="0.2"/> the average in sixty-one to ninety <pause dur="0.5"/> is two-hundred-and-forty-two days <pause dur="0.6"/> # <pause dur="0.3"/> for central parts of England <pause dur="0.6"/> # <pause dur="0.3"/> and you can see <pause dur="1.4"/> that <pause dur="0.3"/> how <pause dur="1.1"/> the sixty-one to ninety average <pause dur="0.3"/> year <pause dur="0.4"/> # is higher <pause dur="0.2"/> than <pause dur="0.6"/> the last <pause dur="0.5"/> # <pause dur="0.3"/> a-hundred-and-fifty years <pause dur="0.4"/> and how <pause dur="1.4"/> <kinesic desc="indicates board on wall using a stick" iterated="n"/> apart from a little dip <pause dur="0.6"/> # <pause dur="1.4"/> in <pause dur="0.8"/> in the sort of seventies

we've gone up <pause dur="0.5"/> # <pause dur="0.7"/> with growing seasons increasing in that <pause dur="0.3"/> in length and that's again <pause dur="0.5"/> predicted to continue <pause dur="3.4"/> linked with that <pause dur="0.5"/> # <pause dur="1.7"/> are some <pause dur="1.9"/> some <trunc> li </trunc> interesting data actually recorded from upper one person's garden in in in Norfolk <pause dur="0.5"/> # <pause dur="0.6"/> but <pause dur="0.3"/> a lady's been growing plants # <pause dur="0.5"/> in in the same place for sort of forty years and has kept detailed records <pause dur="0.5"/> of of flowering dates and things <pause dur="0.4"/> # <pause dur="0.2"/> so <pause dur="0.3"/> these are flowering dates of things like primrose <pause dur="0.6"/> daffodil <pause dur="0.6"/> et cetera <pause dur="0.3"/> # <pause dur="0.2"/> and <pause dur="0.2"/> just showing <pause dur="0.9"/> # <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.2"/> how <pause dur="0.2"/> in general <pause dur="1.0"/> flowering dates are advanced <pause dur="0.7"/> over the last <pause dur="0.2"/> fifty years <pause dur="0.5"/> # <pause dur="1.2"/> primrose <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.2"/> actually flowering first flowering in November <pause dur="0.4"/> # <pause dur="0.6"/> daffodils going from March back into February <pause dur="0.5"/> # <pause dur="0.2"/> and these are the changes per

<pause dur="0.2"/> decade <pause dur="0.2"/> so <pause dur="1.3"/> there's no doubt that growing seasons and times of things are are changing <pause dur="0.6"/> # <pause dur="2.2"/> and and # as temperatures increase <pause dur="2.4"/> # <pause dur="2.5"/> i haven't got <pause dur="0.2"/> time today at all to look at <pause dur="1.0"/> natural vegetation in any great detail at all <pause dur="0.3"/> # <pause dur="0.5"/> but obviously <pause dur="0.8"/> many species are temperature dependent <pause dur="0.6"/> and <pause dur="1.5"/> in general <pause dur="0.7"/> most natural species will <pause dur="0.2"/> probably move <pause dur="1.5"/> northwards in in a very general sense <pause dur="0.6"/> # <pause dur="0.4"/> until they run out of space <pause dur="0.2"/> # <pause dur="0.4"/> and and <pause dur="0.8"/> can't go any further <pause dur="0.4"/> # <pause dur="0.4"/> and these are again people are are producing models of how species distribution <pause dur="0.4"/> # be affected by climatic change <pause dur="0.7"/> most are driven by temperature <pause dur="0.2"/>

but <pause dur="0.3"/> some impact of water <pause dur="0.6"/> # <pause dur="0.5"/> so this this is the sort of present distribution of <trunc> br </trunc> beech trees in in in the U-K <pause dur="0.5"/> # <pause dur="1.0"/> <gap reason="inaudible" extent ="0.7 sec"/> the Chilterns for examples but restricted to the southern areas <pause dur="0.5"/> # <pause dur="0.3"/> and these are various scenarios <pause dur="0.5"/> depending <pause dur="0.8"/> what will happen in two-thousand # or could happen by two-thousand-and-twenty <pause dur="0.4"/> # <pause dur="0.2"/> depending upon the rate of C-O-two emissions <pause dur="0.4"/> a relatively low scenario or a high scenario <pause dur="0.4"/> and by two-thousand-and-fifty <pause dur="0.8"/> # <pause dur="0.5"/> with the same scenarios <pause dur="0.2"/> and basically <pause dur="0.4"/> # <pause dur="1.7"/> the the evidence is that there <unclear> will be </unclear> a northward movement <pause dur="0.3"/> say it's not going to occur to all species but that's an example <pause dur="0.3"/> of what people are people are doing <kinesic desc="changes power point slide" iterated="n"/> <pause dur="3.9"/> # <pause dur="2.9"/> okay <pause dur="0.2"/> i want to focus down a little bit more <pause dur="0.3"/> on on on <pause dur="0.2"/> U-K at the moment <pause dur="0.3"/> and <pause dur="0.7"/> you may or may not have <pause dur="0.4"/> come across this report and i'll show you how to get it on the web <pause dur="0.2"/> later on <pause dur="0.3"/> # <pause dur="1.4"/> that <pause dur="1.2"/> obviously climatic # change is is a great concern <pause dur="0.3"/> and <pause dur="1.0"/> # <pause dur="0.9"/> these people all together the #

<pause dur="0.8"/> U-K climate impact programme DEFRA <pause dur="0.5"/> the Tyndall centre is actually # <pause dur="0.5"/> a centre for climatic change and research which is <pause dur="0.3"/> based at at <pause dur="0.3"/> a few universities particularly East Anglia <pause dur="0.3"/> and the met office <pause dur="0.4"/> have been doing work on <pause dur="0.6"/> scenarios for the U-K now these may not show very clearly <pause dur="0.3"/> here but <pause dur="0.5"/> # <pause dur="1.6"/> # basically what they <pause dur="0.2"/> they do is <pause dur="0.2"/> take <pause dur="0.3"/> big global climate models we <pause dur="0.9"/> talked about very briefly last week <pause dur="0.8"/> # which give you the big picture <pause dur="0.6"/> of of <pause dur="0.2"/> climatic change in the future <pause dur="0.4"/> and then they sort of <pause dur="0.8"/> <trunc> con </trunc> scale them down to smaller scales <pause dur="0.7"/> # <pause dur="0.6"/> by various sort of statistical <pause dur="0.6"/> methods # which we didn't really worry about was that an attempt to give

more detail <pause dur="0.4"/> at at a local scale <pause dur="0.3"/> and <pause dur="0.6"/> # <pause dur="1.0"/> as i say there's a there's there's a reference there where you can find the whole <pause dur="0.3"/> report <pause dur="0.4"/> # if you want to <pause dur="0.4"/> the U-K <pause dur="0.6"/> # <pause dur="0.3"/> climates impacts programme <pause dur="0.6"/> # <pause dur="0.7"/> and <pause dur="1.1"/> the sort of things that it <pause dur="2.2"/> # <pause dur="0.6"/> says <pause dur="0.2"/> the <trunc> g </trunc> change you're going to get <pause dur="0.7"/> # <pause dur="0.4"/> are things like this now <pause dur="0.5"/> this is <pause dur="0.2"/> quite interesting looking at winter <pause dur="0.5"/> # <pause dur="1.1"/> what we've got here are are winters this is this'll be

if you like the mean winter <pause dur="0.7"/> and then <pause dur="0.2"/> we we have warm winters <pause dur="0.7"/> and cooler winters <pause dur="0.4"/> # <pause dur="0.2"/> or wetter winters and dry winters <pause dur="0.7"/> and <pause dur="0.5"/> the black dots are what we've had <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.7"/> # <pause dur="0.4"/> over recent times over <pause dur="0.7"/> # <pause dur="0.4"/> last twenty or thirty years <pause dur="0.6"/> # <pause dur="0.6"/> we've had some winters that <kinesic desc="indicates board on wall using a stick" iterated="n"/> are <pause dur="0.6"/> # <pause dur="0.9"/> sort of drier and colder <pause dur="0.6"/> than than the average <pause dur="0.4"/> # or we have warmer <kinesic desc="indicates board on wall using a stick" iterated="n"/> wetter <pause dur="0.9"/> winters but not particularly so <pause dur="1.1"/> the <pause dur="0.3"/> the circles <pause dur="1.0"/> # sorry the the red symbols <pause dur="0.3"/> # are what's likely to happen <pause dur="0.3"/> by the time you get <pause dur="0.5"/> # <pause dur="0.7"/> into <pause dur="0.6"/> two-thousand-and-twenties and two-fifties and the eighties <pause dur="0.7"/> # <pause dur="0.2"/> and but

<pause dur="0.2"/> with # <pause dur="1.1"/> various bits of <trunc> s </trunc> of scatter <pause dur="0.3"/> and essentially <pause dur="1.2"/> the the implications are for what we talked about last week that we're going to be having warmer and wetter winters <pause dur="0.6"/> # <pause dur="0.4"/> and considerably <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.5"/> warmer and wetter <pause dur="0.5"/> # <pause dur="1.0"/> # <pause dur="0.7"/> by the end of the century <pause dur="2.7"/> if you look at summer <pause dur="0.5"/> # <pause dur="0.6"/> the points tend to be all cluttered <kinesic desc="indicates board on wall using a stick" iterated="n"/> round there that we <pause dur="0.6"/> tend <pause dur="1.0"/> we've had <pause dur="1.1"/> dry <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.3"/> summers <pause dur="0.2"/> and wetter summers <pause dur="0.2"/> but we don't actually have so much variation in temperature <pause dur="0.2"/> over over the summer as a whole <pause dur="0.7"/> # <pause dur="0.7"/> but that again is is likely to change and all the predictions are <pause dur="0.5"/> remember we said last week of a decrease in in rainfall in the summer <pause dur="0.4"/> and the increase in temperature <pause dur="0.3"/> so <pause dur="0.3"/> the evidence <kinesic desc="indicates board on wall using a stick" iterated="n"/> seems to be for the U-K that we are certainly moving <pause dur="0.5"/> towards <pause dur="0.5"/> # <pause dur="1.1"/> warmer drier summers <pause dur="0.4"/> which will have <pause dur="0.6"/> obviously effects upon natural vegetation crops water resources and things like that <pause dur="2.4"/> any any thoughts about that any questions about that does

it <pause dur="4.5"/> <unclear> good for going to the beach </unclear> but then again not so good for <pause dur="0.6"/> other things <pause dur="1.7"/> # <pause dur="1.8"/> again i i don't expect you to look at these in in in any any detail <pause dur="0.5"/> # <pause dur="1.0"/> but these are <pause dur="0.4"/> the sort of level of detail that people are now modelling <pause dur="0.3"/> the climatic change of the U-K <pause dur="0.3"/> you see the U-K is made up of little <pause dur="0.4"/> little grids <pause dur="0.7"/> # <pause dur="1.0"/> and <pause dur="0.7"/> this is looking at winter <pause dur="0.6"/> rainfall <pause dur="0.5"/> # <pause dur="0.8"/> and then summer rainfall over here <pause dur="0.6"/> # <pause dur="0.6"/> and <pause dur="1.7"/> this is <pause dur="0.2"/> # <pause dur="1.2"/> looking at what they think is a is a reasonable scenario and given <pause dur="0.3"/> the present rate of C-O-two emissions and things what's likely to happen <pause dur="0.4"/> and <pause dur="0.2"/> basically <pause dur="0.3"/> # <pause dur="0.7"/> anything

<pause dur="0.5"/> green or blue means more rainfall <pause dur="0.9"/> # <pause dur="0.6"/> and <pause dur="0.5"/> anything yellow down to red brown means less rainfall <pause dur="0.7"/> so <pause dur="0.8"/> # <pause dur="2.4"/> and <pause dur="0.5"/> sorry what i didn't say <pause dur="0.6"/> i can't see here quickly this top line is for <pause dur="0.5"/> sorry for <trunc> re </trunc> relatively low emissions and high emissions <pause dur="0.5"/> of C-O-two and <pause dur="0.4"/> you know we may be somewhere in between <pause dur="0.4"/> but it this quantifies the effects and the important thing is that <pause dur="0.5"/> # <pause dur="0.7"/> in terms of winter rainfall <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.7"/> it seems that most of the effects are going to be concentrated in the in the south and south east

<pause dur="1.1"/> of of of <pause dur="0.7"/> of the country <pause dur="0.5"/> # <pause dur="2.2"/> and <pause dur="0.5"/> the same is going to be true in in <pause dur="1.0"/> summer rainfall <pause dur="0.7"/> that the summer rainfalls will decrease everywhere <pause dur="0.5"/> but <pause dur="0.5"/> # <pause dur="0.4"/> there's a <pause dur="0.5"/> more a tendency of bigger effects in in the south <pause dur="0.7"/> # <pause dur="0.9"/> # <pause dur="0.2"/> and particularly as you get towards the end of the century <pause dur="0.6"/> so <pause dur="0.3"/> these are the sort of latest predictions that people have got and and <pause dur="0.5"/> people are trying to think of the implications of of these things for <pause dur="0.2"/> for <pause dur="0.6"/> for life in the U-K <pause dur="1.6"/> # <pause dur="2.5"/> temperature again <pause dur="0.4"/> # <pause dur="1.6"/> all the colours here are positive <pause dur="0.6"/> # nought's down here <pause dur="0.5"/> # <pause dur="0.2"/> going up to <trunc> f </trunc> <pause dur="0.6"/> four and a half degrees five degrees increase in in temperature <pause dur="0.6"/> # <pause dur="1.4"/> and obviously

<pause dur="0.8"/> high emissions have a bigger effect <pause dur="0.6"/> # <pause dur="0.9"/> but again <pause dur="0.8"/> there's there's a # <pause dur="2.4"/> a a tendency again <pause dur="0.3"/> for the for the <pause dur="0.7"/> well <pause dur="0.3"/> for England i suppose and particularly for the south east # <pause dur="0.4"/> to have the biggest effects <pause dur="0.5"/> # <pause dur="0.5"/> moderated in in in in in in in in other places <pause dur="4.7"/> # <pause dur="1.2"/> soil moisture content this is this is # <pause dur="1.7"/> # <pause dur="1.5"/> very small you can <trunc> r </trunc> read the details on on the web if you want to <pause dur="0.4"/> but essentially again <pause dur="0.3"/> it's

<pause dur="0.4"/> # <pause dur="0.9"/> getting drier essentially in in in in in the average soil moisture content <pause dur="2.7"/> # <pause dur="0.7"/> thermal growing season i <trunc> s </trunc> showed you figures how that've changed over time already <pause dur="0.6"/> # <pause dur="0.9"/> and <pause dur="1.4"/> again we're talking about fairly <pause dur="0.8"/> long changes <pause dur="0.5"/> # big changes # <pause dur="2.0"/> that <pause dur="0.7"/> increases <pause dur="0.5"/> # <pause dur="0.9"/> i mean the lowest colour <pause dur="0.6"/> # <pause dur="1.4"/> i mean <pause dur="0.4"/> # this is for two-thousand-and-eighty so i suppose it's it is the end of <pause dur="0.3"/> getting towards the end of the century <pause dur="0.4"/> # <pause dur="0.8"/> but i mean the smallest changes here are something like an increase in thirty <pause dur="0.6"/> thirty thirty-five days <pause dur="0.6"/> # under low

emissions <pause dur="0.7"/> # <pause dur="0.8"/> and # <pause dur="1.0"/> under high emissions <pause dur="0.8"/> basically temperatures being <pause dur="0.4"/> probably <pause dur="1.5"/> warm enough for <pause dur="0.5"/> substantial crop growth throughout throughout the year <pause dur="0.7"/> so again it's going to have a major effect upon upon vegetation and and cropping <pause dur="2.2"/> # <pause dur="2.4"/> people are doing all sorts of different approaches to try to predict the effects of <pause dur="0.4"/> of climatic change <pause dur="0.5"/> # <pause dur="2.3"/> one one of the nicest studies that <pause dur="0.9"/> i've seen recently is is this one from Ireland <pause dur="0.5"/> # <pause dur="0.3"/> so i thought i'd stick it in to give an idea of what people actually do <pause dur="0.3"/> it uses the same sort of ideas as as before <pause dur="0.4"/> # <pause dur="0.2"/> a big general circulation model and then <pause dur="0.2"/> coming down to give you more <pause dur="0.7"/> local detail <pause dur="0.7"/> # <pause dur="1.0"/> and it uses something called weather

generators <pause dur="0.5"/> # <pause dur="0.2"/> the idea <pause dur="0.2"/> there is that if you sort of estimate the the monthly <pause dur="1.6"/> temperatures for instance or the monthly rainfall <pause dur="0.6"/> you've got an idea of how many <pause dur="0.7"/> days it's going to rain <pause dur="0.8"/> you can generate <pause dur="0.3"/> the daily <pause dur="0.5"/> artificial daily data if you like to simulate <pause dur="1.2"/> typical <pause dur="0.2"/> climate patterns <pause dur="0.5"/> quite a bit of research getting into that sort of area <pause dur="0.4"/> # <pause dur="0.2"/> how you take sort of monthly data <pause dur="0.2"/> and <pause dur="0.9"/> guess at what the daily data will be so it all adds up together <pause dur="0.4"/> if that makes makes sense <pause dur="0.4"/> # <pause dur="0.8"/> because obviously it matters a bit # <pause dur="1.4"/> you know if you if you get <pause dur="0.7"/> sixty millimetres of rain a month does that come in one storm

<pause dur="0.5"/> # which has <pause dur="0.8"/> probably nasty effects and damaging effects or <unclear> does it </unclear> come in <pause dur="0.4"/> in ten <pause dur="0.8"/> nice gentle rain days spread over the month and things like that <pause dur="0.2"/> so there's work going on there <pause dur="0.6"/> # <pause dur="1.2"/> so <pause dur="0.7"/> it tries to estimate daily data <pause dur="0.2"/> and then <pause dur="1.0"/> uses crop models # <pause dur="0.4"/> these are a set of crop models that are very widely used <pause dur="0.4"/> throughout the world <pause dur="0.2"/> to estimate yields <pause dur="0.6"/> # <pause dur="0.5"/> so <pause dur="1.4"/> what they've done is to try to <pause dur="0.6"/>

look at <pause dur="0.6"/> patterns of rainfall <pause dur="0.6"/> in # in Ireland <pause dur="0.5"/> # <pause dur="1.0"/> and <pause dur="0.2"/> they they <pause dur="0.2"/> sort of tested it by <pause dur="1.0"/> going back to predict the past climate if you like <pause dur="0.6"/> # <pause dur="1.3"/> this isn't real data it's predictions from <pause dur="0.7"/> a model <pause dur="0.7"/> with sort of run <pause dur="1.0"/> from from from early on in in in time <pause dur="0.4"/> # <pause dur="0.5"/> and <pause dur="0.2"/> don't worry about the details but basically <pause dur="0.3"/> # <pause dur="1.0"/> January <pause dur="0.2"/> these examples of January rainfall <pause dur="0.2"/> basically getting wetter in Ireland the the darker colour <pause dur="0.2"/> the the more rainfall <pause dur="0.4"/>

but summer rainfall <pause dur="0.5"/> # again decreasing <pause dur="0.2"/> consistent with the U-K <pause dur="0.7"/> # <pause dur="1.6"/> but what does that do to <pause dur="0.4"/> to crop yield oh that's that's temperature sorry <pause dur="0.3"/> # <pause dur="1.5"/> again these are all positive <pause dur="0.2"/> temperatures <pause dur="0.3"/> # <pause dur="3.1"/> # <pause dur="1.0"/> but basically <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.9"/> lighter colours here increasing temperatures in in summer <kinesic desc="indicates board on wall using a stick" iterated="n"/> and increasing <kinesic desc="indicates board on wall using a stick" iterated="n"/> temperatures in <pause dur="0.7"/> in <pause dur="0.9"/> in # winter <pause dur="1.8"/> but then using that data <pause dur="0.5"/> # <pause dur="0.4"/> you can basically run the crop model to estimate the yields that you'd get

<pause dur="0.7"/> for the crops <pause dur="0.5"/> # <pause dur="0.7"/> in each of these little squares <pause dur="0.2"/> you know so each square <kinesic desc="indicates board on wall" iterated="n"/> basically <pause dur="0.3"/> has got its own <pause dur="0.3"/> climate <pause dur="0.6"/> # <pause dur="0.2"/> generated and produces its own estimates in yield <pause dur="0.6"/> # <pause dur="1.1"/> so this is a pattern <pause dur="0.3"/> # nineteen-sixty-one to ninety <pause dur="0.7"/> and <pause dur="0.2"/> basically <pause dur="0.6"/> these conditions <pause dur="0.7"/> # <pause dur="0.7"/> given that barley <pause dur="0.2"/> is is basically grown as a winter crop <pause dur="0.7"/> # <pause dur="1.8"/> so sown in the autumn and harvested later on in in in in the <trunc> s </trunc> in <pause dur="0.4"/> in <pause dur="0.2"/> in the summer <pause dur="0.4"/> #

<pause dur="0.3"/> you're actually tending to get increases in yield <pause dur="0.7"/> in in in barley <pause dur="0.3"/> predicted <pause dur="0.3"/> # <pause dur="1.1"/> in in in Ireland <pause dur="1.0"/> potatoes <pause dur="1.0"/> without irrigation # <pause dur="0.7"/> which <pause dur="0.4"/> are quite widely grown in Ireland at the moment <pause dur="0.5"/> # <pause dur="1.3"/> the colours get lighter basically as time goes on <pause dur="0.4"/> because the summer <pause dur="0.7"/> water shortage becomes more and more <pause dur="0.4"/> # <pause dur="0.9"/> important <pause dur="0.3"/> and and restricts the growth <pause dur="0.2"/>

# of of of <pause dur="0.2"/> the yield <pause dur="0.7"/> so <pause dur="0.2"/> don't worry about the details now i've really put it just put it in to show you <pause dur="0.3"/> what people are doing how people are trying to <trunc> im </trunc> <pause dur="0.2"/> model predict the impacts <pause dur="0.6"/> # <pause dur="1.8"/> but to my mind it's very crucial that the the the <pause dur="0.3"/> the assumptions about rainfall are are are good <pause dur="0.6"/> and i've still got a big question mark over that <pause dur="0.4"/> # <pause dur="0.6"/> you know you still have to trust the <pause dur="0.4"/> the the models or whatever <pause dur="0.4"/> # <pause dur="0.3"/> and they're certainly getting better # they're doing very well but <pause dur="0.4"/> the results are very sensitive to <pause dur="0.6"/> to to to rainfall <pause dur="2.6"/> # <pause dur="3.5"/> as i say we we could spend the whole module

<pause dur="0.6"/> looking at the effects of climatic change <pause dur="0.2"/> just <pause dur="0.9"/> some some very general thoughts about the the likely effects upon agriculture generally in in in <pause dur="0.2"/> U-K whatever <pause dur="0.8"/> different crops <pause dur="0.4"/> basically being grown in different places <pause dur="0.5"/> # <pause dur="0.4"/> is the obvious way of adapting <pause dur="0.2"/> # <pause dur="1.5"/> and # <pause dur="2.8"/> # you know that in some ways may actually give us more diversity and more things that we can actually grow <pause dur="0.9"/> there's probably going to be more autumn sown crops because the winter conditions are going to be warmer different

weeds likely to to be there <pause dur="0.9"/> among the growing seasons <pause dur="0.5"/> and summer water supply may well be a problem <pause dur="0.2"/> # <pause dur="0.3"/> there's going to be a lot of work about efficient irrigation and things to to make use of water resources <pause dur="0.7"/> # <pause dur="2.0"/> so <pause dur="0.2"/> # <pause dur="1.0"/> and in these sort of impact studies you can read much more about these these particular details <pause dur="1.4"/> # <pause dur="2.4"/> rainfall <pause dur="0.4"/> well <pause dur="1.4"/> the predictions all seem to be reduced summer rainfall <pause dur="0.6"/> # <pause dur="0.2"/> will effect water supply <pause dur="0.5"/> and <pause dur="0.3"/> warmer temperatures will really increased demand <pause dur="0.6"/> and i know that the <pause dur="0.7"/> # <pause dur="0.2"/> water companies and and people are very concerned about <pause dur="0.3"/> possible demand in in in <pause dur="1.0"/> two-thousand-and-fifty whatever <pause dur="0.4"/> # <pause dur="0.7"/> and need <trunc> in </trunc> increased

reservoir capacity <pause dur="0.2"/> # to keep the the the <pause dur="0.3"/> winter <pause dur="0.7"/> water <pause dur="0.5"/> # available <pause dur="0.7"/> # <pause dur="1.3"/> a <kinesic desc="indicates board on wall" iterated="n"/> possible adverse effect if water flows in rivers in the summer are cut down and they adversely effect quality <pause dur="0.4"/> pollutants don't get so <pause dur="0.6"/> <trunc> dilu </trunc> diluted and things like that in in effect quality <pause dur="0.5"/> # <pause dur="0.5"/> and fairly obviously <pause dur="0.5"/> heavier more intense winter rainfall can <pause dur="0.4"/> give increased flooding et cetera

<pause dur="0.3"/> and there's evidence over the Europe that these things have become more frequent <pause dur="0.4"/> in in in in time <pause dur="2.1"/> # <pause dur="1.3"/> i'm not going to say much about sea-level rise # <pause dur="1.0"/> but i <pause dur="0.2"/> put here <pause dur="0.4"/> figures from <pause dur="0.6"/> the # <pause dur="0.7"/> the <trunc> U </trunc> U-K <pause dur="0.4"/> climatic impact <trunc> re </trunc> report <pause dur="0.6"/> # <pause dur="0.5"/> and <pause dur="1.4"/> it it's not quite a straightforward picture # we talked about sea-level rise <pause dur="0.4"/> # <pause dur="0.2"/> you know because of the thermal expansion of the ocean and things like that <pause dur="0.5"/> # <pause dur="0.2"/> we also have to bear in mind <pause dur="0.4"/> # <pause dur="0.3"/> that land's also rising as well <pause dur="0.6"/> # <pause dur="0.7"/> in well in in in in

in parts of the U-K <pause dur="0.3"/> # <pause dur="0.6"/> there're <pause dur="0.7"/> geological movements <pause dur="0.3"/> # <pause dur="0.5"/> here in in in millimetres per year <pause dur="0.5"/> # <pause dur="0.2"/> so Scotland's going up <pause dur="1.0"/> very gently <pause dur="0.4"/> # <pause dur="0.2"/> and other parts are going down et cetera <pause dur="0.5"/> # <pause dur="0.6"/> and <pause dur="1.4"/> you have to take that into account when you look at the effects on on on actual <pause dur="0.2"/> practical sea-level rises <pause dur="0.5"/> so <pause dur="0.4"/> these are the sea-level rises that are being predicted for the various areas <pause dur="0.6"/> of the U-K <pause dur="0.4"/> # <pause dur="2.3"/> but again <pause dur="0.9"/> # <pause dur="1.3"/> you know if we if we take # <pause dur="1.0"/> where shall we take take eastern England which is

<pause dur="0.4"/> somewhere that people are often very concerned about <pause dur="0.2"/> that's actually sort of <pause dur="0.5"/> sinking down a bit <pause dur="0.4"/> but we've we've still got a big range between twenty-two <pause dur="0.4"/> centimetres <pause dur="0.7"/> # <pause dur="0.2"/> and eighty centimetres depending upon the different <pause dur="0.3"/> emission scenarios <pause dur="0.6"/> # <pause dur="1.6"/> so again a great cause for concern <pause dur="0.6"/> # <pause dur="1.1"/> and this this is very much a lower limit <kinesic desc="indicates board on wall " iterated="n"/> of i think <pause dur="0.3"/> # of what <pause dur="0.4"/> is likely to happen <pause dur="0.5"/> # <pause dur="0.3"/> so again <pause dur="1.0"/> people looking at <pause dur="0.2"/> you know <pause dur="0.9"/> precautions <trunc> wh </trunc> <pause dur="1.0"/> can't spell coastal can i <pause dur="1.0"/> sorry <pause dur="0.2"/> deliberate mistake <pause dur="1.0"/> # increased coastal flooding coastal erosion <pause dur="0.8"/> and things like that and things to be concerned about <pause dur="4.8"/> right <pause dur="0.5"/> that was really concentrating on the U-K <pause dur="0.4"/> # <pause dur="0.8"/> just to finish up <pause dur="1.1"/> a couple of slides about # world

production <pause dur="0.8"/> # <pause dur="1.5"/> this is looking at <pause dur="0.3"/> # <pause dur="1.3"/> U-K production <pause dur="0.2"/> sorry <pause dur="1.0"/> cereal production in the world <pause dur="0.5"/> under different <pause dur="0.3"/> # <pause dur="0.7"/> climatic change models <pause dur="0.4"/> # <pause dur="0.2"/> you needn't worry about these these are three different models one one's the U-K model and whatever <pause dur="0.4"/> # <pause dur="1.1"/> because the <pause dur="0.2"/> the models don't necessarily agree <pause dur="0.3"/> but <pause dur="0.6"/> the question is

do you get consistency on on on on the output <pause dur="0.2"/> et cetera <pause dur="0.5"/> and <pause dur="0.9"/> # <pause dur="0.8"/> what this graph is is basically looking at is <pause dur="1.0"/> developed countries <pause dur="0.3"/> # <pause dur="0.3"/> developing countries and and the world total <pause dur="0.6"/> and <pause dur="2.5"/> overall <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="0.5"/> # <pause dur="0.3"/> in terms of cereal production <pause dur="0.4"/> the climatic effects only <pause dur="0.7"/> which are are basically temperature and rainfall <pause dur="1.9"/> the the estimates seem to be that <pause dur="1.7"/> total developed world <pause dur="0.7"/> cereal production should go down <pause dur="0.6"/> but <pause dur="1.4"/> i'm sorry <trunc> i </trunc> if you can't read the detail but # <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="1.2"/> the climate effects are are rainfall # and temperature <pause dur="0.6"/> the the

<gap reason="inaudible" extent ="0.3 sec"/> effects of carbon dioxide <pause dur="1.0"/> increase will probably <pause dur="0.6"/> turn that into into a positive effect <pause dur="0.7"/> # <pause dur="0.8"/> so <pause dur="1.2"/> increased <kinesic desc="indicates board on wall" iterated="n"/> temperature reducing yield <pause dur="0.2"/> but the carbon dioxide effects <pause dur="0.6"/> generally balancing that although <pause dur="1.0"/> depending on which climate scenario you you you pick up <pause dur="0.7"/> # <pause dur="0.3"/> you may have a a negative effect or positive effect <pause dur="0.5"/> # <pause dur="0.5"/> but then <pause dur="1.7"/> there are various

things that we can do <pause dur="0.5"/> # <pause dur="1.3"/> this is a <unclear> dash </unclear> # called adaptation level one <pause dur="0.3"/> which are things like <pause dur="0.4"/> # <pause dur="0.5"/> changing the crop variety changing the planting date <pause dur="0.6"/> # <pause dur="1.2"/> # and the amount of water applied for a <pause dur="0.3"/> level <trunc> a </trunc> areas already irrigated <pause dur="0.7"/> # <pause dur="0.7"/> so we can do some things to <pause dur="0.3"/> to <pause dur="0.5"/> maintain cereal supplies <pause dur="0.5"/> # <pause dur="1.3"/> or we can <pause dur="1.6"/> grow <pause dur="0.5"/> go on to further adaptation by growing different different <trunc> varie </trunc> different crops <pause dur="0.4"/>

you know maybe growing <pause dur="0.5"/> # <pause dur="1.1"/> well say more maize instead of instead of wheat and things like that <pause dur="0.5"/> # and other things <pause dur="1.2"/> but i suppose the the basic picture to get from from here is that <pause dur="0.5"/> # <pause dur="2.3"/> that in theory the developed world can probably <pause dur="0.5"/> maintain its food supplies its cereal supplies <pause dur="0.5"/> by <pause dur="0.2"/> <trunc> a </trunc> <pause dur="0.3"/> adapting changing varieties moving things around <pause dur="0.5"/> # <pause dur="0.6"/> that's much less harder to do or much harder to do in developing countries <pause dur="0.3"/> where the scope for <pause dur="0.3"/>

adaptation is less <pause dur="0.6"/> # <pause dur="0.3"/> adaptation may reduce <pause dur="0.3"/> things but the <pause dur="0.3"/> the climatic effects <pause dur="0.2"/> particularly in the tropics <pause dur="0.6"/> would seem to be <pause dur="0.2"/> generally fairly negative <pause dur="0.4"/> and that's a <pause dur="0.5"/> a position that we need to <pause dur="0.6"/> need to think about <pause dur="0.8"/> # <pause dur="0.7"/> in terms of world <pause dur="0.2"/> total <pause dur="0.7"/> well maybe we can <pause dur="0.3"/> keep <pause dur="0.3"/> food supplies <pause dur="1.1"/> together <pause dur="0.2"/> # <pause dur="0.3"/> at # <pause dur="0.8"/> the same sort of level <pause dur="0.4"/> # <pause dur="1.5"/> but <pause dur="0.2"/> # <pause dur="0.2"/> you know there's there's a tale of two two worlds there if you like and # <pause dur="0.7"/> the world's got to be able to

come to terms with this particular problem in in in the near future <pause dur="2.7"/> # <pause dur="2.2"/> again <pause dur="0.5"/> a couple of international studies to show that people are looking at these things around the world <pause dur="0.5"/> # <pause dur="1.7"/> the the current distribution of beech trees in in in north America <pause dur="0.4"/> # <pause dur="0.7"/> and <pause dur="0.2"/> how that's likely to change under different <pause dur="0.2"/> predictions of of climatic change in the next <pause dur="0.5"/> # <pause dur="1.6"/> # fifty years or so <pause dur="0.5"/> # <pause dur="0.7"/> simple things like <pause dur="0.9"/> again i've just picked out one individual crop <pause dur="0.2"/> this is coffee <pause dur="0.4"/> # <pause dur="1.4"/> quite an important crop in in parts of Uganda <pause dur="0.7"/> # <pause dur="0.9"/> coffee doesn't really like warm temperatures <pause dur="0.5"/> # <pause dur="1.8"/> there's a lot of material out there that that you can read <pause dur="0.4"/> # you don't really need to read for <pause dur="1.4"/> for boring things

like the exams in this course and things like that <pause dur="0.5"/> # <pause dur="0.5"/> you know the hand outs and some of the particular things i'll i'll talk about exams a bit later on <pause dur="0.4"/> # <pause dur="0.4"/> but <pause dur="0.3"/> these are some of the the important sites for climatic change <pause dur="0.5"/> # <pause dur="0.8"/> the grid what we we we've referenced before <pause dur="0.5"/> # <pause dur="0.5"/> <kinesic desc="indicates board on wall" iterated="n"/> which is the United Nations environment programme <pause dur="0.6"/> # <pause dur="0.5"/> that <kinesic desc="indicates board on wall" iterated="n"/> one we had up <pause dur="0.2"/> # <pause dur="0.4"/> we had sort of climatic graphics with last week <pause dur="0.5"/> climatic research East Anglia <kinesic desc="indicates board on wall" iterated="n"/> is is is quite an important one <pause dur="0.6"/> met office <pause dur="0.2"/> # <pause dur="0.5"/> U-K <pause dur="0.5"/> World Meteorological Organization in in Switzerland <pause dur="1.0"/> # is W-M-O <pause dur="0.6"/> # <pause dur="0.3"/> this is the United Kingdom <pause dur="0.5"/> # <pause dur="0.5"/> climatic impacts programme <pause dur="0.9"/> the Tyndall centre

<pause dur="0.3"/> # <pause dur="0.3"/> again is set up for for mainly for U-K <pause dur="0.2"/> climate change <pause dur="0.6"/> and again <pause dur="0.2"/> DEFRA has has got an important web site now for for climatic change information <pause dur="0.8"/> # <pause dur="1.2"/> so i hope i sort of took your interest and <pause dur="0.9"/> go away and have a look at some of these things because it really is a <pause dur="0.5"/> a substantial problem we all <pause dur="0.2"/> challenge shall we say that's going to <pause dur="0.7"/> affect <pause dur="1.1"/> you in your lives much more than me in <pause dur="0.7"/> in respect to mine i suppose <pause dur="0.5"/> # <pause dur="2.0"/> okay any any thoughts or questions or <pause dur="3.5"/> cameras are very good at shutting people off <gap reason="inaudible, multiple speakers" extent="1.5 sec"/> <pause dur="3.3"/> you pessimistic about the future optimistic about the future or what <pause dur="2.6"/> </u>

<u who="sm1360" trans="pause"> we die <gap reason="inaudible" extent="0.5 sec"/> <pause dur="0.7"/> </u> <u who="nm1359" trans="pause"> sorry <gap reason="inaudible" extent="0.5 sec"/> <pause dur="3.3"/> yeah there's there's there's a lot of uncertainties there but but the science is is really focusing # it's # <pause dur="0.5"/> it is a major major concern area <pause dur="1.6"/> # and i i hope <pause dur="0.3"/> what you can see is some of the sort of basic principles that we looked at early on in the course the sort of energy and exchange <pause dur="0.7"/> and <pause dur="0.4"/> # net radiation <pause dur="1.0"/> things like the microclimate modification radiation <unclear> is that </unclear> they've all got a part in understanding and predicting what's going on <pause dur="0.4"/> and i think that's quite quite important <pause dur="3.9"/> okay # <pause dur="1.7"/> well # <pause dur="1.2"/> any any other questions on this or not <pause dur="1.2"/> yeah <pause dur="0.3"/> </u>

<u who="sm1361" trans="pause"> <kinesic desc="raising hand" iterated="n"/> # in page six # this one here <kinesic desc="indicates the handout" iterated="n"/> about the <pause dur="0.3"/> natural variation in the <pause dur="0.3"/> # red one <unclear> report to come </unclear> winter and summer <pause dur="0.2"/> </u> <u who="nm1359" trans="pause"> yeah <pause dur="0.4"/> </u> <u who="sm1361" trans="pause"> # <trunc> y </trunc> there's some where there all dots seem to be all together of what <pause dur="0.2"/> the # <pause dur="0.5"/> natural ones <pause dur="0.3"/> </u> <u who="nm1359" trans="pause"> # yeah i'm sorry you i should have <pause dur="0.6"/> warned you that <pause dur="0.2"/> </u> <u who="sm1361" trans="pause"> i don't know how <pause dur="0.6"/> i i i can see how # <pause dur="0.4"/> the # <pause dur="1.1"/> # <pause dur="0.3"/> </u> <u who="nm1359" trans="pause"> yeah </u> <u who="sm1361" trans="latching"> i can see how the they could they could manage to get the the red ones what to come on the left hand side by looking at the black ones but i don't see how <pause dur="0.3"/> to get the black ones all come together <unclear> they might </unclear> manage to get somewhere <pause dur="1.3"/> </u> <u who="nm1359" trans="pause"> so # are you do you mean do you mean these ones or <pause dur="0.2"/> </u> <u who="sm1361" trans="pause"> other side <pause dur="0.3"/> </u> <u who="nm1359" trans="overlap"> so this one </u> <u who="sm1361" trans="overlap"> looks like <pause dur="0.2"/> the ones which they've actually got <pause dur="0.2"/> # </u>

<u who="nm1359" trans="latching"> yeah </u> <u who="sm1361" trans="latching"> what to <pause dur="0.2"/> i i don't see how they got the # <pause dur="0.3"/> ones that are all spread out <pause dur="1.2"/> </u> <u who="nm1359" trans="pause"> scenarios for what will happen in in two-thousand-and-twenty <pause dur="1.0"/> and <pause dur="0.5"/> what it's basically saying is that <pause dur="1.7"/> that temperatures temperatures are going to be warmer and summers are going to be dryer <kinesic desc="indicates board on wall using a stick" iterated="n"/> <pause dur="2.3"/> # <pause dur="1.6"/> # i'm not answering the question there i think but <pause dur="0.5"/> # <pause dur="1.0"/> so that's two-thousand-and-twenty <kinesic desc="indicates board on wall using a stick" iterated="n"/> and then <pause dur="0.5"/>

two-thousand-and-fifty we'd might be down here two-thousand-and-eighty we're going to be down here <pause dur="0.6"/> # <pause dur="0.6"/> so <trunc> the </trunc> these are different estimates from different different sort of scenarios so there's variability <pause dur="0.9"/> # <pause dur="1.0"/> what <kinesic desc="indicates board on wall using a stick" iterated="n"/> he's really saying is that <pause dur="1.6"/> by two-thousand-and-twenty we're probably going to be experiencing summers <kinesic desc="indicates board on wall using a stick" iterated="n"/> that <pause dur="0.3"/> we haven't experienced before <pause dur="1.0"/> </u> <u who="sm1361" trans="pause"> well it <pause dur="0.9"/> </u> <u who="nm1359" trans="pause"> # <pause dur="0.3"/> whereas here there is some overlap <pause dur="0.6"/> # <pause dur="0.3"/> so <pause dur="0.4"/> some of the winters <pause dur="0.2"/> #

<pause dur="0.4"/> in in two-thousand-and-twenty won't be that different from winters we've

had <pause dur="1.1"/> in recent times <pause dur="1.0"/> # <pause dur="0.2"/> you know we we've had <kinesic desc="indicates board on wall" iterated="n"/> <pause dur="0.2"/> things of this <pause dur="0.2"/> amount of warmth and this amount of of of rainfall <pause dur="1.0"/> # <kinesic desc="indicates board on wall" iterated="n"/> <pause dur="1.6"/> it's <pause dur="0.3"/> later on <pause dur="0.2"/> two-thousand-and-fifty when we're going to get into <pause dur="0.6"/> # <pause dur="0.2"/> even warmer and wetter <pause dur="2.0"/> # conditions <pause dur="0.2"/> # <pause dur="0.6"/> is that a sort of answer </u> <u who="sm1361" trans="latching"> think so </u> <u who="nm1359" trans="latching"> yeah <pause dur="1.4"/> </u> </body> </text> </TEI.2>