Global warming has taken a heavy toll on major cereal crops and since 1981 it has caused a loss of $5 billion.
According to a study conducted by David Lobell, researcher of the Lawrence Livermore National Laboratory in the US, from 1981-2002 fields of wheat, corn and barley throughout the world have produced a combined 40 million tonnes less per year because of increasing temperatures caused by human activities.
Though the impacts are relatively small compared to the technological yield-gains over the same period, the results demonstrate that negative impact of climate trends on crop yields at the global scale are already occurring.
Most experts believe that adaptation by farmers to climate change would lag several years behind climate trends, because of the difficultly in distinguishing climate trends from natural variability.
A key to move forward is to study how well cropping systems can adapt to a