Depicting the extent of drought in the U.S. can be a tricky task. The U.S. Drought Monitor is a tool authored by various individuals from the National Oceanic Atmospheric Association (NOAA), U.S. Department of Agriculture (USDA) and the National Drought Mitigation Center. However, it’s a resource that recently sprouted complaints that it’s too slow in accurately predicting the current level of drought.
USDA meteorologist Brad Rippey said he understands the complaints, but assured that the U.S. Drought Monitor is still an accurate tool, as it doesn’t use a single piece of data, but many layers of data and information to compile the latest results each week.
“I've been working with the U.S. Drought Monitor for almost 20 years and we started out with just two or three different tools that we looked at, said Rippey. “Now in our toolbox we have several dozen different tools we look at. Some of them are observational things like temperatures or precipitation. We also use satellite based information. From what we get from our satellites and then we have a number of computational indices that are calculated, and I have to say all of them really we push them all together. We crunch them we layer them and that's how we come up with that drought monitor depiction every week.”
He said by using a “convergence of evidence” approach, it allows the authors to see the various levels of drought and gauge the change from one week to the next.
It’s what he considers “flash drought” as something that drought monitor doesn’t pick up quickly. “Flash drought” occurs within 7 to 10 days, something not always shown when looking at long-term dryness. For example, the current Drought Monitor shows northwest Indiana is practically drought-free. However, local farmers are reporting extreme crop stress from little to no rain over the past few weeks. He said reports from the field help the authors understand local impact.
“I'll admit we are still learning how to do the drought monitor and even after 20 years we still rely very much on these boots on the ground impacts to help fine tune the analysis,” said Rippey.
AgDay/U.S. Farm Report meteorologist Mike Hoffman said he finds value in the drought monitor, but also uses the rootzone moisture map from NASA to measure dryness across the country when giving his forecast.
“It's a government product, and I find it extremely useful because when you're talking about the flash drought, it it's not waiting on the data to be compiled,” said Hoffman. “It is an immediate thing that seems to be fairly accurate to me.”
Rippey said the drought monitor looks at rootzone moisture, as well as several other tools. What the drought monitor is lacking is funding. Rippey said the monitor relies on individuals who help author the picture of dryness each week, but financial resources aren’t set aside solely for the drought monitor.
“In the past 20 years we have always operated on no additional funding other than our specific job description,” said Rippey. “So obviously we all are paid a salary for our jobs, but there is no dedicated funding for the drought monitor even after 20 years.”
It’s that lack of funding Sen. John Thune (R-SD) tried to address in the 2018 Farm Bill. Thune introduced the “Improved Soil Moisture and Precipitation Monitoring Act of 2018,” which he said is legislation that would improve the drought monitor’s accuracy. He said that would also help USDA become more prompt in granting livestock grazing assistance and other drought-related programs.
“South Dakota farmers and ranchers are familiar with working through extreme weather conditions, especially drought,” said Thune. “And after the 2016 and 2017 drought conditions in much of Western South Dakota, some of them would probably say they’re all too familiar with it and are very concerned about accurate precipitation measurement. I recently heard some of those concerns firsthand, which is what led to the development of this legislation.”
Thune said he thinks the Act will help make the drought monitor a more effective and efficient tool, while ensuring USDA programs are using accurate data in administering drought-related programs.