Oppsummering: En studie har etablert at global oppvarming kan øke landsbruksareal med hele 44 % i den boreale(nordlige) del av kloden ved år 2100. Men økt tempertur vil også øke nedbør og fordampning i mer sydlige områder som vil forandre vannbalansen globalt og produserer mer tørke i disse områdene. Dette vil trolig skape mer ustabile landbruksforhold i mange områder.
However, the scientists warn that the same climate trends that would increase land suitable for crop growth in that area could significantly change the global climatic water balance - negatively impacting agriculture in the rest of the world.
Scientists from the University of Leeds in the UK assessed the impact of climate change on land that could support agriculture in the boreal region, which includes large sections of Canada, Sweden, Norway, Finland, Russia and the US.
They found that the upper edge of land suitable for crop growth could shift as far north as 1,200km from the current position with the most dramatic changes occurring in the inner-continental regions of North America and Eurasia.
Currently only 32 per cent of the boreal region falls into 'growing degree days' - the climate parameter linked to crop growth - and rainfall requirements for small cereal crops, such as oats and barley.
Using global climate models the team was able to predict the future extent of growing degree days and changes in rainfall.
The study, published in the journal Scientific Reports, estimates that by 2099 roughly 76 per cent of the boreal region could reach the right conditions for agriculture.
However, the study also warns that while total rainfall will generally increase on an annual basis, a warmer climate will also lead to more evaporation with potentially dramatic impact on the climatic water balance, both geographically and across seasons.
For example while the inner continental regions would suffer drought conditions during the summer, the regions around the ocean's rims could see an increase in water available to crops.
Additionally, regions that would suffer temporary summer droughts might see wetter autumns which would have a negative impact on the harvest season.
"Climate change will have a profound impact on our agricultural regions. A projected consequence is the loss of farmland and crops from areas that are currently productive, which is cause for concern regarding long term global food security," said Joseph Holden, a professor at the University of Leeds.
"Therefore we need to know whether in northern high latitudes new areas will become suitable for crops," Holden said.
Kilde: Global Warming Policy Foundation