Will climate change make the U.S. Midwest drier or wetter during the summer growing season? A new Dartmouth-led study finds that the answer remains uncertain.
The findings are important given the Midwest's agricultural output is critical to the U.S. economy and global food security.
The study appears in the journal Water Resources Research. A PDF is available on request. The study included researchers from Dartmouth College, Columbia University, National University of Singapore and Massachusetts Institute of Technology.
A potential consequence of climate change is significant modification of the water cycle in farming areas, such as the Midwest. Multiple studies have investigated the response of surface air temperature and precipitation to climate change across the Midwest and United States, but few studies have examined the response of soil moisture and still fewer have assessed soil moisture using a combination of model simulations and regional observations. Soil moisture is a key indicator of the water cycle, reflecting dynamics of precipitation, evaporation, plant transpiration and runoff.
The Dartmouth-led team ran multiple regional climate model experiments to project summertime changes in the water cycle over a representative area of the Midwest. Some of their experiments predict drier soil conditions over the Midwest, while others predict wetter soil conditions, with the response strongly dependent on the choice of global climate model used to provide input to the regional climate model.
To resolve the contradictory predictions, the researchers also assessed an extensive and unique observational dataset of the water budget in Illinois. Their results show no statistically significant trends in soil moisture, precipitation, streamflow, groundwater level or surface air temperature over a recent 26-year period. Model simulations unanimously project increased temperatures in the Midwest, but the observed trend has been insignificant so far in contrast to climate trends across the world, where most places have already warmed significantly.
"Based on our analysis of model simulations and regional observations, we conclude that climate change impacts on the water cycle of the Midwestern United States remain uncertain," says lead author Jonathan Winter, an assistant professor of geography at Dartmouth, whose research explores climate prediction and the impacts of climate variability and change on water resources and agriculture.
"Our findings also suggest that while increases in surface air temperatures have been insignificant so far, adaptation to projected increases in temperature should be given priority as the signal is robust and could have large impacts on crop yields. Our findings highlight the need for expanded observations of soil moisture and improved simulations of soil moisture by climate models."
Dartmouth Assistant Professor Jonathan Winter is available to comment at Jonathan.M.Winter@dartmouth.edu.
Broadcast studios: Dartmouth has TV and radio studios available for interviews. For more information, visit: http://www.
John Cramer | EurekAlert!
Amputees can learn to control a robotic arm with their minds
28.11.2017 | University of Chicago Medical Center
The importance of biodiversity in forests could increase due to climate change
17.11.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong
Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...
An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications
Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...
Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.
The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
11.12.2017 | Physics and Astronomy
11.12.2017 | Earth Sciences
11.12.2017 | Information Technology