Heavy rain events increasing in the US; Tri-Cities too
The race weekend forecast looks wet at times. In fact, last year was incredibly wet. More than three inches of rain fell in a span of three days, causing nearly widespread flooding across the area and at the track itself.
According to the folks at Climate Central, these heavy rain events are increasing across the U.S. That includes the Tri-Cities.
While there's certainly fluctuation from year-to-year, the overall trend shows an increase in days with 0.5, 1, and 2 inches of rain in our area.
For instance, the average number of days per year when one inch of rain falls is eight days. In six of the last ten years, we have seen more than that average.
Why is that the case? Climate scientists continue to attribute these heavy rain events to a warming climate. Some of you may be saying, "Oh, here we go again!" This claim, however, is backed by science and by multiple research attempts.
In a warming world, there's more evaporation from bodies of water and transpiring plants. For every 1 of warming, the saturation level of the atmosphere goes up by 4%. This means that there's more water available to condense into precipitation.
This is something I just read about this morning. A study done by the Department of Atmospheric and Environmental Sciences at SUNY Albany shows a link between Precipitable Water and temperature. As temperature rises, the amount of water that can completely condense increases. As you can imagine, the amount of Precipitable Water in heavy rain events is higher than in your garden-variety "chance of rain" days. So a rise in Precipitable Water would imply a rise in heavy rain events.
All in all, Climate Central shows that the largest increase in heavy rain events across the US has been in the northeast. This coincides with the SUNY Albany research mentioned above. Taken directly from that journal article, "...the areas with large positive PW trends generally have warming trends, such as the U.S. Northeast, Europe, Australia, the central North and South Pacific, and the southern Indian Ocean."
Why does this matter? Since 2010, there has been $39 billion in damage related to heavy rain events. That does not include tropical cyclones.
Source: Wang, Junhong. "Global Water Vapor Trend from 1988 to 2011 and Its Diurnal Asymmetry Based on GPS, Radiosonde, and Microwave Satellite Measurements." Journal of Climate. 2016. Web. 11. Apr. 2018