Climate Impact on Global Food

RTXT6KS615Press release by the Potsdam Institute for Climate Impact Research

Global food markets: Climate impacts would be more costly than bioenergy effects

Ambitious greenhouse-gas mitigation consistent with the 2 degrees target is likely to require substantial amounts of bioenergy as part of the future energy mix. Though this does not come without risks, global food markets would be affected much more by unmitigated climate change than by an increased bioenergy demand, a study led by scientists from the Potsdam Institute for Climate Impact Research (PIK) now finds. Agricultural prices could be about 25 percent higher in 2050 through direct climate impacts on crop yields in comparison to a reference scenario without climate change. By way of contrast, a high bioenergy demand as part of a scenario with ambitious mitigation appears to raise prices only about 5 percent.

 The analysis has been published along with two other studies led by PIK in the course of the Agricultural Model Intercomparison and Improvement Project (AgMIP) in a Special Issue of the journal Agricultural Economics. The results show agriculture to be in the spotlight of climate change, both in terms of its need to adapt to climate impacts and its potential to mitigate global warming. Agricultural production and land-use change contribute about one third to global greenhouse-gas emissions.

First AgMIP study: Second-generation bioenergy to decarbonize the transport sector   

“Second-generation bioenergy may become relevant especially in the longer term for reducing carbon emissions – for instance as biofuels in the transport sector, because other technical low-emission options such as electrification are relatively expensive,” lead-author Hermann Lotze-Campen says. Today’s bioenergy production of currently around 40 ExaJoule worldwide is dominated by traditional wood for heating and first-generation transport fuels like ethanol from sugar cane or bio-diesel from oil crops. While first-generation biofuels directly compete with food and feed production, second-generation biofuels have the potential to reduce that competition between food and energy markets and to also reduce production costs.

Global demand for second-generation bioenergy from crop and forest residues, wastes or purpose-grown plants like Miscanthus grass or poplar trees is assumed in the study to rise to about an additional 100 ExaJoule in 2050 (about 15 percent of total primary energy demand), if global warming is supposed to be limited to about 2 degrees above pre-industrial levels. Conducting a comparison between five agro-economic simulations, the study allows for the first time for a tentative conclusion that ambitious climate change mitigation with bioenergy need not drive up global food prices much.

Second AgMIP study: Global warming repercussions increase need for additional cropland

In a comprehensive comparison of ten global agro-economic simulation models, Christoph Schmitz from PIK examined how much cropland will be used under different socioeconomic and climate change scenarios. “We find most models projecting an increase in cropland by 2050 that is more than 50 percent higher in scenarios with unabated climate change than in those assuming a constant climate,” Schmitz says. The increase would be 320 million hectare instead of approximately 200 million hectare – the difference equals roughly three times the size of Germany. Across all simulations, most of the cropland expansion takes place in South America and Sub-Saharan Africa. “Now this could be bad news as in those regions, in order to gain additional cropland, centuries-old rainforests are cut down. This does not only increase carbon emissions but also harms biodiversity and threatens important ecosystem services,” Schmitz explains.

So far projections of future land use have shown widely varying results due to large uncertainties in data and methods. To better understand the differences, the ten leading international modeling teams in this field sat together over a period of two years to learn from each other. The result is this unique multi-model comparison, which allows for more robust assessments and a better understanding of the connections between climate change, land use and agricultural prices.

Third AgMIP study: Effects on crop yields are strong, but vary widely across the globe

Future crop productivity and the role of climate impacts for economic simulations of food markets are at the center of a third study. Using a comparison of computer simulations, the study examines the challenges in quantifying in which regions climate change affects land productivity to which extent. “Potential climate change impacts on crop yields are strong but vary widely across regions and crops,” lead-author Christoph Müller from PIK says.

For the five major crops, i.e. rice, wheat, maize, soybeans and peanuts, the study finds a climate-induced decrease in yields of 10 to 38 percent globally until 2050 in a business-as-usual scenario of rising greenhouse-gas emissions, compared to current conditions. In terms of adaptation, there’s no one-fits-all response. Production could be shifted to regions with lower negative climate impacts; some other regions may profit from an intensification of agriculture. “To be able to cope with the big differences from one region to another, and from one crop to another, a more flexible global agricultural trading system would be needed,” Müller says.

A major step towards more robust assessments of climate impacts on agriculture

There are still considerable uncertainties in future agricultural projections – such as the CO2 fertilization effect, availability of additional agricultural land, or future rates of productivity increase. Yet the AgMIP results are a major step forward towards more robust climate impact assessments for agriculture. “Droughts like the one in 2012 in the United States can have huge impacts on crop production and exports,” Lotze-Campen says. “This illustrates that bad harvests in major production regions, even though limited in scope, can have significant impacts on global agricultural markets, prices and food security. This effect is likely to amplify under unabated climate change.”

Article: Lotze-Campen, H., von Lampe, M., Kyle, P., Fujimori, S., Havlík, P., van Meijl, H., Hasegawa, T., Popp, A., Schmitz, C., Tabeau, A., Valin, H., Willenbockel, D., Wise, M. (2013): Impacts of increased bioenergy demand on global food markets: an AgMIP economic model intercomparison. Agricultural Economics (early view/online) [doi:10.1111/agec12092]

Weblink to article: here

 Article: Schmitz, C., van Meijl, H., Kyle, P., Nelson, G.D., Fujimori, S., Gurgel, A., Havlík, P., Heyhoe, E., Mason d’Croz, D., Popp, A., Sands, R., Tabeau, A., van der Mensbrugghe, D., von Lampe, M., Wise, M., Blanc, E., Hasegawa, T., Kavallari, A., Valin, H. (2013): Land-use change trajectories up to 2050: insights from a global agro-economic model comparison. Agricultural Economics (early view/online) [doi:10.1111/agec.12090]

Weblink to article: here 

Article: Müller, C., Robertson, R.D. (2013): Projecting future crop productivity for global economic modeling. Agricultural Economics (early view/online) [doi:10.1111/agec.12088]

Weblink to article: here

About AgMIP: The Agricultural Model Intercomparison and Improvement Project (AgMIP) is a major international effort linking the climate, crop, and economic modeling communities with cutting-edge information technology to produce improved crop and economic models and the next generation of climate impact projections for the agricultural sector. It includes researchers at institutes including the Potsdam Institute for Climate Impacts Research (PIK), the International Food Policy Research Institute (IFPRI) and the International Institute for Applied Systems Analysis (IIASA), among others.

Weblink to AgMIP:
Weblink to IFPRI:
Weblink to IIASA:

 For further information please contact:
PIK press office
Phone: +49 331 288 25 07
Twitter: @PIK_Climate

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Comment on “Climate Impact on Global Food”

  1. Here we go again with poor old Potsdam. About all they get right, apparently, are their many appeals for money. They know their audience. Quick, run and tell the king. The sky is falling again or is it still? Without extremism and alarmism the funding dries up.

    Where is the actual news? The very dullest amongst us is able to figure out that any and all future agricultural projections contain “considerable uncertainties.” Well duh, fortune telling is like that. How much land more or less will be in use? What will be the effect of CO2 fertilization? What will be the rates of productivity? Since nobody can really know for a certainty they just input what works for their theory of the day. “Droughts like the one in 2012 in the United States can have huge impacts on crop production and exports.” Well yeah, but then so will hurricanes, tornados, volcanic eruptions and tsunamis but who’s asking? Unpredictable, day to day weather affects crops wherever they grow.

    Somehow they are able, after much deep thinker type thought, to conclude that “bad harvests in major production regions, even though limited in scope, can have significant impacts on global agricultural markets, prices and food security.” You think? “This effect is likely to amplify under unabated climate change.” You betcha and if that change happens to be global cooling instead of warming I’m guessing the results won’t be too good either. Either way Potsdam is right the way a stopped clock is right twice a day.

    In the frozen north, and it is well frozen this year from coast to coast, Chrysler bought into the warming theory and is now back ordered on water pumps. Guess what? The new ones all froze. The models didn’t predict winter here in Canada I guess.

    The trouble with models is, has and forever will be is that they can only ‘predict’ from their input. They cannot predict the unknown and as they say, “shit happens.” Good things happen too, of course, though the climate programmers would never allow for that. Where would the money come from then? Good times earn nothing. Go figure.

    I notice too that the new Potsdam models keep pushing the Dooms Day dates back beyond the lifetime of their sponsors and me but what the hell, they may be, might be, could be, you know, one day correct. If we only just predict far out enough maybe the earth will burn to a crisp or maybe freeze over again. Both are possible and have been modelled but then, what hasn’t? Now we’re out to 2050 with no real disaster in sight.

    I’m still enjoying how 74 Global warming scientists and advocates plus their ships and crews found themselves stuck in the Antarctica ice that wasn’t supposed to be there. They even had an ice-strengthened ship to prove to the world that man-made global warming had caused the ice to disappear. Oops! It’s a great story as they managed to get stuck in the ten foot thick sea ice they claimed had melted away. A hundred years ago, explorer Douglas Mawson got within 50 yards of shore in a wooden ship with only a sextant. He was stopped not by ice but by water too shallow for his ship. He then traveled 300 miles inland. Our climate heroes equipped with an ice-breaker, GPS navigation, on-board Internet, radar and satellite communications only got within miles of shore. How could that be? They were stopped by miles, I repeat, miles of ice. Ice!

    Arctic ice was up 29% last year. It froze up in August this year trapping several boats and other intrepid scientists and explorers in search of a balmy beach or Japan, who really knows? They sure didn’t.

    The overall volume of Antarctic ice is the highest in thirty-five years. Where are the models? Hey, it’s SUMMER in Antarctica! Someone should have told the climate scientists. Apparently they didn’t know. Of course in summer the ice sheet can retreat hundreds of miles. All you would expect to see then would be melting sea ice and calving glaciers. These are the films they like to show to demonstrate global warming. Oh the horror! It happens every year and has since the beginning of time or ice or whichever came first.

    Another Ice Age may actually come in another few hundred years. Hell, we’re only 164 years removed from the last one, the Little Ice Age I keep reminding people caused the Hudson, the Thames and the Seine to freeze over.

    Closer to home, Lake Ontario, the Great Lake that forms the border between Canada and the U.S. is a very deep lake and rarely freezes. Between 10% and 90% of the lake area, depending on the severity of the winter, typically develops an ice sheet. These sheets form along the shoreline and in calm water bays, where the lake is much shallower. Like the Arctic and Antarctica, Lake Ontario has seen cold weather before freezing completely over in 1830, 1874, 1893, 1912 and 1934. The ice sheet coverage during the winters of 1877 and 1878 was up to 95–100% in most of the lake. We have seen ice this year too but do not fear the coming of another ice age anytime soon. Neither are we anticipating extra-long summers. Up here we prefer to think we have 8 months of winter followed by 4 months of bad sledding. There seems to be no change in sight other than the winters are becoming colder and there is more snow. I’m a kid again!

    Throughout history there have been numerous Ice Ages followed by long periods of warming. Climate is like that. It’s cyclical. These Ice Ages always began with elevated CO2 levels the fear mongers and climate modelers are unable to blame on bad corporations and evil gas companies as they didn’t exist unlike the ice in Antarctica which does, even in summer. Ask the climate scientists. They’ve been there, they know. They may not admit it but they know.

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