On the Buffalo

Climate change and our river

For years (Kyoto 1997, Copenhagen 2009, Paris 2015), scientists and politicians have stressed the importance of holding global warming increases to less than 1.5 degrees Celsius (2.7 degrees Fahrenheit).

Scientific climate models have gotten much more sophisticated and accurate over the years, now showing that the 1.5 degrees Celsius goal is hopeless, and that under current policy, a 2.8 degrees C (5 degrees F) increase is likely by the end of the century.

Nations of the world continue to squabble and finger-point, mostly producing lofty goals which are then unfulfilled for lack of commitment and cooperation. Meanwhile the business community has become expert at greenwashing, claiming unsubstantiated environmental progress.

Not every hurricane, flood, drought, or big fire is due to climate change. While the current global temperature increase due to CO2 and greenhouse gas emissions has been rapid by cosmological time, a direct link to climate change is hard to document without extensive long-range historical records.

Consider our beloved Buffalo National River, which, while 153 miles long, still only drains 2% of Arkansas. Floods on the Buffalo are impressive, such as the 53-foot rise Dec. 3, 1982, which ran over the Arkansas 14 bridge. Every other year on average, there is a 20-foot rise at St. Joe. But there is no strong evidence that flood intensity is increasing over the last 80 years; it might just be the nature of the river and surrounding steep topography.

On the other hand, according to United States Geological Service (USGS) data collected every 15 minutes at various locations along the Buffalo, the yearly average flow has increased by a surprising 16% in the last 80 years. During the same period, precipitation at Harrison increased by about 5% (climate change?) which might account for some of the increased flow, but there could be other reasons. And while it is difficult to take the temperature of a river, data from the USGS and the Buffalo National Park suggest that water temperatures have increased over a period of 48 years, perhaps by as much as 3 degrees F.

Are there consequences to these changes?

There are some 221 different amphibians and reptiles in Arkansas, and 75 or so fish species in the Buffalo River watershed. How might climate change affect them? A good example is the alligator snapping turtle, which lives in many streams in Arkansas, including the Buffalo. The turtles are large, reaching more than 150 pounds, and slow-growing, reaching sexual maturity at about 13 years. They have protected status as an endangered species. Their home range is limited, and they can’t easily migrate to avoid global warming problems.

They are also a Temperature Dependent Sexual Determination (TDSD) species like lots of other turtles and reptiles. The gender of offspring is not determined at inception but rather by nest temperature: If temperature is higher than 87 degrees F, almost all offspring are female; and if temperature is lower than 81 degrees F, then almost all offspring are males. So, have nest temperatures actually been increasing with resulting gender imbalance, or are they capable of adapting to climate change as the world’s humans will have to do? And how about the effect on the premiere species, smallmouth bass? And how about nuisance algae on the river?

No one seems to have definitive answers.

While the debate about how best to address climate change problems continues, it is important for us in Arkansas to have our universities and state agencies have adequate financial resources to properly and extensively gather data, analyze and model the results, and make reasonable projections for the future.

Solid data gathered from the Buffalo not only serves the interests of our first national river and its 1.5 million yearly visitors, but provides information that will help us understand ongoing changes in other Ozark streams.

It’s a great investment in Arkansas heritage and the growing economic footprint in outdoor recreation.