What will the world look like in 50 years? Everybody wants to know the answer, especially when it comes to climate change.
But it’s not just about how the temperature will change and how nature will react; it’s how people will react (or won’t) to those changes. Take farmers: How will they respond to hotter and drier growing conditions, as predicted by climate change?
My colleague Evan Girvetz and I just finished an in-depth look at how the use of irrigation in the United States might change in response to climate change. Here’s what we found:
+ Most of the United States will get drier with climate change.
+ For past drought events farmers, somewhat logically, installed more irrigation equipment and put more water down on fields that were already irrigated.
+ If past trends are an indication of farmers’ responses to climate change, then we can expect that there will be more irrigated area and more water withdrawals for agriculture in the future.
What I have been pondering recently is how difficult it is for most people to really visualize how different the world might be in 50 years.
It is relatively straight-forward to look at the climate change forecasts from the General Circulation Models (GCMs) and then calculate a potential impact on irrigation if irrigation technology and agricultural practices stay the same.
But they won’t, of course.
And I have noticed a tendency in people, including me, to underestimate the kinds of radical ways farmers might respond to climate change.
Crop Switching: It’s Not a New Thing in the United States
For instance, crop switching — will farmers choose to grow different crops that fare better in drier conditions and require less water?
In our analysis, we assumed some crop switching based on past trends. But it’s still really difficult for people used to the agricultural economy of today to imagine, for instance, wheat fields in the Dakotas switching to another crop because it is warmer.
From a historical perspective though, we shouldn’t be too surprised if something like that happened. Over very long time scales, agriculture changes in the United States a lot.
Consider how settlement of the U.S. Midwest totally changed the agricultural economy of New England. New England used to produce corn and wheat and it doesn’t now, since it is uneconomical. We shouldn’t be surprised if climate change also drives a large process of crop switching. There are reports, for instance, of the Midwest drought of last year pushing farmers to switch forage production from corn to sorghum.
Switching from Rain to Irrigation
Another finding of our study is that, in some areas of the country, places that conduct rain-fed agriculture now might switch over to using irrigation, at least in some fields for some crops.
For instance, a place like Indiana — the prototypical example of rain-fed agriculture — would need to start using more irrigation. This is hard to imagine for some people who are used to today’s farming economy. Yet there are signs of how farmers might respond to this change already: In Iowa, for instance, last year’s drought led to increasing sales of new irrigation equipment.
This transformation could have huge implications on government spending on irrigation — for example, over long time frames, farmers have responded to droughts by organizing to demand the government to build irrigation systems, in some cases transporting water over long distances.
Getting Irrigation Incentives Right: Hard to Imagine, But Not Impossible
There has been a trend toward increased irrigation efficiency in the United States over the last two decades. If this trend continues, it would actually offset a lot of the climate change-induced increase in water withdrawals. It needn’t involve fanciful new technologies, just more full application of the efficient irrigation technologies we have now.
The crux of the problem is getting the incentives right, so that farmers have a reason to want to invest in more efficient irrigation. Right now, water is free or very cheap for most farmers, so they have relatively little incentive to invest in more efficient irrigation system. Our research suggests that getting the incentives right, and accelerating the trend toward increased irrigation efficiency, could be an important part of adapting to climate change.
It is really difficult right now to imagine the United States having the political will to change its water law and policy enough to insure that incentives are adequately there. But I try to have some humility — who knows what will be political possible in 50 years? If we were sitting around in 1963, would we have been able to predict that in less than 10 years the Clean Water Act would have been passed? Probably not. Yet political will changed quickly then, and it could change quickly now.
Opinions expressed on Cool Green Science and in any corresponding comments are the personal opinions of the original authors and do not necessarily reflect the views of The Nature Conservancy.