Ohio Had a Long Drought in 2007?
The media fallout from the latest National Climate Assessment is the gift that keeps on giving. Over at the Natural Resources Defense Council, apparently climate change is wreaking havoc on agriculture in Ohio. Just take this claim by the NRDC:
"Ohio farmers, for instance, saw corn yields drop by up to 60 percent and first hay harvests by up to 70 percent during the long drought of 2007."
Wait. Ohio had a long drought in 2007? Well, by definition, if it was just in 2007, that isn't a "long drought," is it?
Perhaps a closer look at this "long drought of 2007" in the Buckeye State is needed.
It wasn't even a dry year in Ohio during 2007. The state saw 41.2 inches of precipitation during the calendar year, well above the 20th-century average of 38.3 inches per year. Even the prior twelve-month periods ending in July, August, September, October, and November of 2007 weren't dry. In fact, they were all above average, too.
Indeed, the period from September 2006 through August 2007 was the 18th wettest on record dating back to 1895. A whopping 43.4 inches of precipitation fell over this time-frame, more than 5.1 inches above the 20th-century average.
During 2007, statewide precipitation during March and August was well above average (August was the sixth wettest in the 120-year record), April and July were about average, and May, June, and September were dryer than normal. Sound like a "long drought"? Nope.
In 2007, 84 percent of Ohio's planted corn acreage was in the central, north central, northeast, northwest, and west central agricultural districts. There were no unusually low precipitation amounts in these regions during 2007 during the April to October period. In fact, the largest corn growing acreage region of the state -- the northwest -- saw well above average precipitation in 2007.
The April to October drought index for the northwest portion of the state was the 13th highest (i.e., almost a record non-drought) since 1895. Same extreme non-drought result for the north-central region, as well as the west-central district. The central region (climate division 5) of Ohio was in drought during the 2007 growing season. But it certainly wasn't one to cause climate hysteria. Here are the drought indices for this part of Ohio since 1895 (green is non-drought, yellow is drought; y-axis quantifies magnitude of non-drought/drought severity). See 2007? It's not even remotely close to a historically severe drought. And for comparison, the drought indices for the northwest region (climate division 1) are also provided. Note the extreme non-drought conditions during 2007.
Droughts in these portions of Ohio are also becoming less severe over time, as they are in each and every other climate subdivision of the state. So while the NRDC is concerned about the National Climate Assessment and anthropogenic climate change effects on a supposedly "long drought" in Ohio during 2007, when we actually look at the data we see that 2007 wasn't actually even a drought in half the state's climate divisions, and only a modest drought in the remainder.
In 2008, only one of the state's climate subdivisions saw drought conditions: the northeast hills, and this area was barely (and I mean barely) in a technical drought during 2008 -- ranking only 51st worst out of 119 years (a.k.a., pretty much average). The rest of the state was wetter than normal and most clearly in a non-drought. So much for that "long" component of the 2007 Ohio drought.
Having established that half the climate subdivisions in Ohio weren't even in drought during 2007, and that the other half were only in a very short term minor drought, what effect did Ohio's 2007 "long drought" have on corn and hay yields?
Remember, the NRDC claims that "Ohio farmers, for instance, saw corn yields drop by up to 60 percent and first hay harvests by up to 70 percent during the long drought of 2007."
In 2007, the hay yield for Ohio was 2.42 tons/acre, only down 14 percent from 2006. In 2008 (a uniform non-drought year across the state), the yield was 2.46 tons/acre. The average hay yield since 2007 has been 2.48 tons/acre -- equivalent to that during the supposed "long drought" year that the NRDC claims crushed "first hay harvests by up to 70 percent."
Now corn is serious business in Ohio, worth about $3 billion per year. And what happened to corn yields in 2007? The statewide average was 150 bushels per acre. That was down less than 6 percent from 2006, and was significantly higher than 135 bu/acre in the following non-drought year of 2008. Since 2000, the average corn yield in Ohio has been 148 bu/acre. In other words, the purported "long drought" of 2007 led to an average statewide corn yield.
Corn yields continue to rise in Ohio. In 2013, the state saw its highest ever yield, breaking the record set only a few years prior in 2009. Four of the top five highest ever corn yields have occurred during the last five years (and the drought year of 2012 was ranked 20th highest -- still impressive). All of the top ten Buckeye State corn yields have been seen since 2000. That 2007 "long drought" year? Ranked the 8th highest of all time.
Once again, we see the National Climate Assessment being employed to generate hysteria -- this time, food security hysteria for Americans -- in a manner that simply doesn't hold up to the test of real data scrutiny. These fear-mongering tactics by the activists go on all day, every day, and it appears the scientific community -- many (most?) of whom are activists themselves -- is going right along with the hysterifying. Terrible times at present for rigorous science and evidence-based policymaking.