{"id":3887,"date":"2014-04-04T14:10:12","date_gmt":"2014-04-04T13:10:12","guid":{"rendered":"http:\/\/www.theoillamp.co.uk\/?p=3887"},"modified":"2014-04-04T14:10:12","modified_gmt":"2014-04-04T13:10:12","slug":"one-thing-we-have-learnt-this-week-climate-change-and-food-security","status":"publish","type":"post","link":"https:\/\/www.theoillamp.co.uk\/?p=3887","title":{"rendered":"One thing we have learnt this week- climate change and food security"},"content":{"rendered":"

One thing we have learnt this week is we need to worry about food security due to climate change.\u00a0\u00a0 The Intergovernmental Panel on Climate Change (IPCC) 5th assessment report covers a wide range of issues relating to climate change, but knowing readers of this blog are interested in food I have just decided to cover this one aspect.<\/p>\n

One of the arguments that climate sceptics have made is that increased carbon dioxide levels will increase plant growth.\u00a0 One right wing think tank in the US even produced a video claiming something along the lines “they called pollution we call it fertilizer”. This belief which, to be fair, many climate scientists hoped might be true is presumably based on the overall photosynthetic reaction shown below.<\/p>\n

\"photosynthesis\"<\/a><\/p>\n

For any scientists reading this yes I’m aware its not balanced, its just to keep it very simple.\u00a0 In crude chemistry terms if you increase the concentration one of the reactants on the left hand side then more product should be produced to bring the reaction back into a new state of chemical equilibrium.\u00a0 This is known as the law of mass action.\u00a0 The problem is that plant biochemistry is much more complicated than that indicated by the simple reaction above.\u00a0 For starters the reaction above is split up, water is broken down to hydrogen ions, electrons and oxygen in a plant organ known as the chloroplast and this process requires light.\u00a0 Carbon dioxide is captured to form sugars in light independent reactions (known as the Calvin cycle) by an enzyme called ribulose bisphosphate carboxylase oxygenase (RuBisCO.\u00a0 This protein is probably the most abundant enzyme on earth!\u00a0 Under dry conditions plants will attempt to save water by shutting pores called stomata.\u00a0 This means the carbon dioxide levels fall and the reaction above starts to go into reverse (so maintaining the chemical equilibrium).\u00a0 Various plants have adapted mechanisms to concentrate carbon dioxide and therefore maximise their growth.\u00a0 For example some tropical plants (such as maize) use a an additional chemical pathway called the C4 pathway to chemically “fix” the carbon dioxide making photosynthesis in these plants more effective.<\/p>\n

This last fact could be important to food security. Originally scientists thought plants would grow faster and bigger everywhere as CO2 levels rose.\u00a0 Measurements have not borne this out.\u00a0 Current thinking suggests that the plants in the tropics will suffer and plants in the northern hemisphere will do better.\u00a0 Could it be that in the tropics plants are as efficient as they can be due to pathways like C4?\u00a0 Whatever the reason plants in the tropics don’t benefit from increased CO2.<\/p>\n

This is what the 5th assessment says;<\/p>\n

“Based on these studies, there is medium confidence that climate trends have negatively<\/em>
\naffected wheat and maize production for many regions (Figure 7-2) (medium evidence, high agreement). Since many of these regional studies are for major producers, and a global study (Lobell et al. 2011) estimated negative impacts on these crops, there is also medium confidence for negative impacts on global aggregate production of wheat and<\/em>
\nmaize. Effects on rice and soybean yields have been small in major production regions and globally (Figure 7-2) (medium evidence, high agreement). There is also high confidence that warming has benefitted crop production in some high-latitude regions, such as Northeast China or the United Kingdom Jaggard et al., 2007, Supit et al., 2010;<\/em>
\nChen et al., 2010; Gregory and Marshall, 2012).”<\/em><\/p>\n

If this was it then food security would be increased in temperate regions and decreased in the tropics. \u00a0 Which would be bad enough.\u00a0 The problem is this leaves out one huge elephant in the room – the weather.\u00a0 Different plants are adapted to different levels of sun and moisture (and humans are responsible for much of that adaptation).\u00a0 So for example rice likes growing in water, whereas maize will cope with much drier conditions.\u00a0 The 5th assessment does not reach definite conclusions on this weather related food security\u00a0 issue.\u00a0 In fact it states crop yields and weather are even more complicated and localised than the above might imply.<\/p>\n

“The overall relationship between weather and yields is often crop and region specific, depending on differences in baseline climate, management and soil, and the duration and timing of crop exposure to various conditions. For example, rice yields in China have been found to be positively correlated with temperature in some regions and negatively correlated in others (Zhang et al., 2010). The trade-offs that occur in determining yield are therefore region-specific. This difference may be due to positive correlation between temperature and solar radiation in the former case, and negative correlation between temperature and water stress in the latter case. Similarly, although studies consistently show spikelet sterility in rice for daytime temperatures exceeding 33\u00b0C (Jadadish et al., 2007; Wassmann et al., 2009), some statistical studies find a positive effect of daytime warming on yields because these extremes are not reached frequently enough to affect yields (Welch et al., 2010). Responses to temperature may vary according whether yields are limited by low or high temperatures. However, there is evidence that high temperatures will limit future yields even in cool environments (Semenov et al., 2012; Teixeira et al., 2013).<\/em><\/p>\n

In other words on food security, the official view is we are guessing.\u00a0 Common sense has to come into play here though. As a keen non-professional gardener, since the late 90’s I’ve seen the weather become increasingly erratic.\u00a0 I also know that almost everything I grow needs benign weather.\u00a0 Not to much rain or sun, just the right amount.\u00a0 The crazy weather we have been getting does not bode well in that regard.\u00a0 There are also other issues such as rising demand, population increase and peak oil that must be factored in.\u00a0 Food security looks like being an increasing challenge over the next couple of decades and going forward.\u00a0 We all have a responsibility to stop this happening, as the writer of proverbs says;<\/p>\n

“A good man leaves an inheritance to his children’s children, but the sinner’s wealth is laid up for the righteous.\u00a0 The fallow ground of the poor would yield much food,<\/em>
\nbut it is swept away through injustice.<\/em>” Proverbs 13v22-3<\/p>\n

Neil<\/p>\n

This passage will form the basis of part of a new book we are working on and is a very crude first draft.<\/p>\n","protected":false},"excerpt":{"rendered":"

One thing we have learnt this week is we need to worry about food security due to climate change.\u00a0\u00a0 The Intergovernmental Panel on Climate Change (IPCC) 5th assessment report covers a wide range of issues relating to climate change, but … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[5,9],"tags":[],"class_list":["post-3887","post","type-post","status-publish","format-standard","hentry","category-climate-change","category-food"],"yoast_head":"\nfood security<\/title>\n<meta name=\"description\" content=\"One thing we have learnt this week is we need to worry about food security due to climate change. The Intergovernmental Panel on Climate Change (IPCC) 5th assessment report covers a wide range of issues relating to climate change, knowing readers of this blog are interested in food I have just decided to cover this one aspect.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.theoillamp.co.uk\/?p=3887\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"admin\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"5 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.theoillamp.co.uk\/?p=3887\",\"url\":\"https:\/\/www.theoillamp.co.uk\/?p=3887\",\"name\":\"food security\",\"isPartOf\":{\"@id\":\"https:\/\/www.theoillamp.co.uk\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\/\/www.theoillamp.co.uk\/?p=3887#primaryimage\"},\"image\":{\"@id\":\"https:\/\/www.theoillamp.co.uk\/?p=3887#primaryimage\"},\"thumbnailUrl\":\"http:\/\/www.theoillamp.co.uk\/wp-content\/uploads\/2014\/04\/photosynthesis2-300x74.jpg\",\"datePublished\":\"2014-04-04T13:10:12+00:00\",\"author\":{\"@id\":\"https:\/\/www.theoillamp.co.uk\/#\/schema\/person\/b6f2831189b0d01294e9672bb540ba6f\"},\"description\":\"One thing we have learnt this week is we need to worry about food security due to climate change. The Intergovernmental Panel on Climate Change (IPCC) 5th assessment report covers a wide range of issues relating to climate change, knowing readers of this blog are interested in food I have just decided to cover this one aspect.\",\"breadcrumb\":{\"@id\":\"https:\/\/www.theoillamp.co.uk\/?p=3887#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.theoillamp.co.uk\/?p=3887\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.theoillamp.co.uk\/?p=3887#primaryimage\",\"url\":\"http:\/\/www.theoillamp.co.uk\/wp-content\/uploads\/2014\/04\/photosynthesis2-300x74.jpg\",\"contentUrl\":\"http:\/\/www.theoillamp.co.uk\/wp-content\/uploads\/2014\/04\/photosynthesis2-300x74.jpg\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.theoillamp.co.uk\/?p=3887#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.theoillamp.co.uk\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"One thing we have learnt this week- climate change and food security\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.theoillamp.co.uk\/#website\",\"url\":\"https:\/\/www.theoillamp.co.uk\/\",\"name\":\"The oil lamp - shining God's light on peak oil\",\"description\":\"Blogging by Neil and Andy about Peak oil and faith.\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.theoillamp.co.uk\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Person\",\"@id\":\"https:\/\/www.theoillamp.co.uk\/#\/schema\/person\/b6f2831189b0d01294e9672bb540ba6f\",\"name\":\"admin\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.theoillamp.co.uk\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/2070f70411f2eab27f08cd0b2332e27e3987c781423ecba6c16b575181ce2a6a?s=96&d=mm&r=g\",\"contentUrl\":\"https:\/\/secure.gravatar.com\/avatar\/2070f70411f2eab27f08cd0b2332e27e3987c781423ecba6c16b575181ce2a6a?s=96&d=mm&r=g\",\"caption\":\"admin\"},\"url\":\"https:\/\/www.theoillamp.co.uk\/?author=1\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"food security","description":"One thing we have learnt this week is we need to worry about food security due to climate change. The Intergovernmental Panel on Climate Change (IPCC) 5th assessment report covers a wide range of issues relating to climate change, knowing readers of this blog are interested in food I have just decided to cover this one aspect.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.theoillamp.co.uk\/?p=3887","twitter_misc":{"Written by":"admin","Est. reading time":"5 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.theoillamp.co.uk\/?p=3887","url":"https:\/\/www.theoillamp.co.uk\/?p=3887","name":"food security","isPartOf":{"@id":"https:\/\/www.theoillamp.co.uk\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.theoillamp.co.uk\/?p=3887#primaryimage"},"image":{"@id":"https:\/\/www.theoillamp.co.uk\/?p=3887#primaryimage"},"thumbnailUrl":"http:\/\/www.theoillamp.co.uk\/wp-content\/uploads\/2014\/04\/photosynthesis2-300x74.jpg","datePublished":"2014-04-04T13:10:12+00:00","author":{"@id":"https:\/\/www.theoillamp.co.uk\/#\/schema\/person\/b6f2831189b0d01294e9672bb540ba6f"},"description":"One thing we have learnt this week is we need to worry about food security due to climate change. The Intergovernmental Panel on Climate Change (IPCC) 5th assessment report covers a wide range of issues relating to climate change, knowing readers of this blog are interested in food I have just decided to cover this one aspect.","breadcrumb":{"@id":"https:\/\/www.theoillamp.co.uk\/?p=3887#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.theoillamp.co.uk\/?p=3887"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.theoillamp.co.uk\/?p=3887#primaryimage","url":"http:\/\/www.theoillamp.co.uk\/wp-content\/uploads\/2014\/04\/photosynthesis2-300x74.jpg","contentUrl":"http:\/\/www.theoillamp.co.uk\/wp-content\/uploads\/2014\/04\/photosynthesis2-300x74.jpg"},{"@type":"BreadcrumbList","@id":"https:\/\/www.theoillamp.co.uk\/?p=3887#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.theoillamp.co.uk\/"},{"@type":"ListItem","position":2,"name":"One thing we have learnt this week- climate change and food security"}]},{"@type":"WebSite","@id":"https:\/\/www.theoillamp.co.uk\/#website","url":"https:\/\/www.theoillamp.co.uk\/","name":"The oil lamp - shining God's light on peak oil","description":"Blogging by Neil and Andy about Peak oil and faith.","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.theoillamp.co.uk\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Person","@id":"https:\/\/www.theoillamp.co.uk\/#\/schema\/person\/b6f2831189b0d01294e9672bb540ba6f","name":"admin","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.theoillamp.co.uk\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/2070f70411f2eab27f08cd0b2332e27e3987c781423ecba6c16b575181ce2a6a?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/2070f70411f2eab27f08cd0b2332e27e3987c781423ecba6c16b575181ce2a6a?s=96&d=mm&r=g","caption":"admin"},"url":"https:\/\/www.theoillamp.co.uk\/?author=1"}]}},"_links":{"self":[{"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/3887","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3887"}],"version-history":[{"count":20,"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/3887\/revisions"}],"predecessor-version":[{"id":3910,"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/3887\/revisions\/3910"}],"wp:attachment":[{"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3887"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3887"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3887"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}