Climate change adaptation: Lessons from 2012
Here's David Lobell at the Chicago Council on Global Affairs:
For all of the talk about the need to adapt to climate change, we still know fairly little about two basic questions: what works best, and how much can adaptation deliver? ....
Why don’t we know more? It would be easy to blame our ignorance on complacency. There is a tendency to marvel at the progress made in agriculture in the past 50 years, and assume it can handle anything....
It is also tempting to blame ignorance on inexperience. After all, many people continue to view climate change as something to deal with in the future. But the evidence is clear that climate has already been changing over the past 30 years in most agricultural areas, and farmers are doubtlessly trying to adapt. Up until now, the United States was an exception to that trend. But the 2012 drought has changed that, and projections indicate that years like this will be increasingly common in the coming decades.
.... why was US agriculture not better prepared for the 2012 drought? And did anything work well that can be scaled up?
A lot has changed in US agriculture since the 1988 drought, and many of the changes were textbook examples of what should help to reduce impacts of hot summers. Farmers now sow corn and soybeans more than a week earlier on average, and use longer maturing varieties than in 1988. Advances in cold tolerance along with spring warming trends allowed corn to expand in northern states where temperatures are cooler.... Carbon dioxide levels, which improve crop water use efficiency, have increased by more than 10% since 1988. And farmers have begun to grow drought tolerant seeds that were unavailable in 1988.
Yet when the 2012 drought arrived, with fairly similar characteristics to 1988, impacts on crop yields were roughly the same. Corn yields are expected to be about 25% below trend, close to the 28% drop in 1988.
What can we learn from this experience? It is too early to say anything definitive, but two explanations seem plausible.....
[see link for the rest]
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