Last year, much of the country, including Nebraska, saw the hottest year on record, along with an ongoing drought. Climate change scientist Cynthia Rosenzweig of the NASA Goddard Institute for Space Studies (see full bio below) says more years like 2012 are projected in the coming decades. Rosenzweig spoke at the 2013 Water for Food Global Conference in Lincoln, Neb., and talked with NET News about her research.
What are some of the major climate change impacts?
ROSENZWEIG: In agriculture, climate change with higher temperatures will shorten growing cycles, thereby reducing yields. It will also bring increased drought around the world, along with intense precipitation events: more floods, more runoff. Climate change, in the long term, is not good for crops.
We’re already beginning to see effects of the warming that we’ve had so far on crops around the world.
How might those changes impact food production?
ROSENZWEIG: A changing climate will eventually bring the need for adaptation. The agricultural practices we have today will need to be modified eventually to keep up with warmer temperatures, and increases in droughts and floods. We have to prepare for changing conditions in agriculture.
Last year, much of the country, particularly the Great Plains, saw the hottest year on record, along with an ongoing drought. What can we expect in the future?
ROSENZWEIG: The drought of 2012 was unusual not only because of lack of precipitation but that combined with high temperatures. That’s exactly what the climate change science is predicting for the future: intensified variability on precipitation, as well as the inexorable rise in temperatures. There are definitely concerns as we come into the coming decades of having more frequent years like 2012, and even worse in terms of higher temperatures.
What do you say to those who say this is a cycle, that there are periods of warming and cooling in the planet’s history and this is just another one of those?
ROSENZWEIG: There have always been changes in the Earth’s climate, over all time scales. But because humans are increasing greenhouse gases, we’re now seeing faster rates of increased change in our climate system than have occurred in the past. And that’s what’s bringing this major challenge for our planet into the forefront.
How will these changes affect rural areas as compared with urban areas?
ROSENZWEIG: Cities are also very much at risk, especially coastal cities. But even inland cities like those in the Great Plains, there’s potential for increased heat waves, which aren’t good, particularly for the elderly. It’s going to change our food systems, both on the producer side—for farmers of the Great Plains, and on the consumer side in the cities, where a growing number of people are living.
How can people adapt?
ROSENZWEIG: Farmers are already adapting, they always adapt to weather of each season, and will continue to do so. The issue with climate change is that those adaptations are going to have to come faster and eventually be larger than the ones that we’re used to.
For example, if the Great Plains becomes much drier, with extreme precipitation, our crop choices may need to switch: more sorghum, less corn. We may need to use more cover crops to hold in moisture. Farming needs to adapt to changing climate but will also be part for the solution through methods like no till, cover cropping that increases carbon in the soil, and being more energy efficient.
A recipient of a Guggenheim Fellowship, Rosenzweig joins impact models with climate models to project future outcomes of both land-based and urban systems under altered climate conditions. She holds a doctorate in plant, soil, and environmental sciences from the University of Massachusetts in Amherst.