Drought Data for Southeastern Ohio, the NOAA’s National Integrated Drought Data Information System (NIDIS), and the U.S. Drought Monitor

     The area where I live in Southeastern Ohio is under an exceptional level of drought, the dryest designation, as of September 5, 2024, as shown on the map below. Rain has also been spotty, which means some areas may have gotten small but rain-packed storms a few weeks ago as I did, but others may have gotten little to nothing in over six weeks or more. Periodic severe droughts are not uncommon to the region. Droughts can lead to lower crop yields for farmers (and gardeners), lower stream and river levels that could impact river transport and other activities, decreased municipal water supply, increased risk to water quality, decreased livestock water availability, and decreased hydropower output. If the ground dries out too deep it can affect building foundations. Wildfire risks rise. 

     The graph below is an Ohio drought map showing the regularity of droughts with some severe. It is a composite of the data of all colors over top of each other. The colors can be turned on or off on the website portal. The graph shows some regularity, but predictability is still limited. It suggests that two years of severe drought in a row are very rare, while two or more years in a row of mild or non-drought conditions are more common. Another suggestion is that wet years are a bit more common than dry ones. But that is only looking at the last 24 years. This is the first year in that 24-year period where D4 occurred and only the third where D3 occurred.

     Below is a graph I filtered from the site to show D4-level droughts from 1895 to the present. This data shows the frequency of D4 events. It appears that a D4-level event occurs about every five years. Most are small in areal coverage. The data also suggest that strong D4 events that covered more aerial extents occurred about seven times in the past 80 years and super strong ones affecting the most area occurred three times in the past 80 years. It appears that this year’s super strong drought is possibly an event that recurs every 25 years or so. The last time it happened was 25 years ago or 36 years ago depending on where you cut it off. Thus, it was probably on schedule or slightly behind schedule. As a gardener, I am keenly aware of droughts, and it has indeed been a while. 

 

     The National Drought Mitigation Center at the University of Nebraska-Lincoln runs the U.S. Drought Monitor which keeps weekly data for states. Below is a table of some of the impacts from D0 through D3 events. The site offers weekly regional summaries, data, time series, graphs, GIS data, and more. One thing that matches the data is that one of the D3 impacts, lawns going dormant, has indeed been happening here for a long time. It was nice not having to mow grass. However, I am worried about some of my perennials. The leaves on some of my trees totally dried up. We'll see what comes up missing next year.  

 

References:

 

U.S. Drought Monitor. Ohio. Ohio | U.S. Drought Monitor (unl.edu)

National Integrated Drought Information System (NIDIS). Ohio. Ohio | Drought.gov