Saturday, September 27, 2014

Climate Change Workshop, part 2.

Saturday morning, after a good cafeteria breakfast (the OU Biological Station is famous for its food), and everyone is in a good mood to start the first full day of the climate change workshop sponsored by Oklahomans for Excellence in Science Education (OESE) and the Oklahoma Climatological Survey. About 20 middle school and high school teachers are participating.

Danny Mattox, a middle school educator, explained how different proxies, such as carbon and oxygen isotopes, can be used to reconstruct past climate. For example, water with the light isotope of oxygen evaporates faster than water with the heavy isotope; therefore during periods of glaciation, water with the light isotope gets removed from the oceans and deposited in glaciers. Ancient ice enriched in the light isotope, or foram shells enriched in the heavy isotope, are indicators of global temperature thousands or millions of years ago. Pollen is also a proxy for climate, since you can distinguish the pollen of plants that grow in cool or moist conditions from pollen of plants that grow in hot or dry conditions.

Then he provided evidence, from his own research, that the Trail of Tears (in particular, the Choctaw Removal) occurred during an unusually cold climate period, based on many independent but convergent climate proxies. This cold period was due to such things as an unusually high number of volcanic eruptions, an El Nino event, and a period of low solar radiation. This caused a very cold winter and contributed to the massive deaths of Natives--weather making an already cruel act perpetrated by the U.S. government even worse.

The next presenter was Alek Krautmann from the Southern Impact Climate Planning Program. Oklahoma has the most weather disaster events relative to the size of the state. Because strong and destructive storms are related to higher temperatures, this situation is nearly inevitable to become worse. This is in addition to the fact that we now have more suburbs, therefore human structures and investment are spread out over more area, susceptible to storm damage. From the NOAA list of billion-dollar disasters, the worst was Hurricane Katrina of 2005. The fact that Katrina was a "category 5" storm offshore and category 3 when it hit land near New Orleans does not tell you all of the interacting disasters that occurred: not just the storm, but levee failure and the breakdown in emergency response, especially when hundreds of thousands of people fled northward from the storm. Earlier storms were less economically destructive because now there is so much coastal development.

This year (2014) seemed pretty mild to us because there were fewer and smaller Atlantic hurricanes; but it was a violent year in the Pacific.

But another source of billion-dollar disasters is drought. Katrina caused $125 billion of damage, and Sandy cost $65 billion, but the 2012 drought caused $30 billion of damage. Droughts may also become more severe and frequent with global warming. Droughts can be measured in different ways; for example, how much agricultural loss occurs, or how much stream flow is lost, or the disparity between supply and demand for human use. In the 1950s drought, Dallas ran out of good water; they had to use brackish water, unless you had a special card to show that you had kidney problems and needed clean water. Texas has had about 40 years of above-normal precipitation, so they were surprised when the ongoing severe drought began in 2011.

The impacts of drought can be very complex; low levels of warm water caused massive "blooms" of harmful "algae" (including cyanobacteria) in Oklahoma and other areas in 2011 and 2012. Though rain has returned to Oklahoma, nearly every reservoir remains low, something that many of us could see by driving to this meeting.  Drought and heat interact: it takes more water to raise corn when it is hot than when it is a little cooler. You can get current and recent historical U. S. drought information at

The average rainfall value means almost nothing; what determines the health of humans and nature is determined by departures from this value, especially multi-year droughts.

We also discussed how we sometimes fail to notice drought because we draw water out of aquifers, which were charged with water mostly at the end of the last ice age. But even here, people are becoming more aware of our water limitations. Texas County, Oklahoma, uses a prodigious amount of water from the Ogalalla Aquifer to raise corn, but this year some of us have noticed that they are not raising as much corn as they used to, perhaps because in the last couple of years the farmers have had to drill over fifty feet deeper just to find irrigation water.

We need scientific measures and explanations to help people understand what is happening with drought. Brad told us about the "Hydro-illogical cycle," which consists of: Rain; apathy; drought; concern; panic; then the rain returns, leading again to apathy.

We must also be careful about the use of statistics. For example, considering a map showing the cumulative number of tornadoes may be biased, since small tornadoes out in the country may go unreported, while they all get reported from urban areas where there are lots of people to observe them and be affected by them. And should we count straight-line wind damage in with tornado damage?

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