Climate change,

tree rings and us

Like a book of factual history, tree rings are the annual chapters of a tree’s life. Through the eyes of a trained professional, tree rings tell the real story of a location through a living thing — the tree. Those rings can yield a lot of information about the climate at a specific location. The oldest trees are the bristlecone pine (pinus longaeva), dating back some five millennia, and they are found at a high elevation in the California desert White Mountain range. I’ve had the opportunity of walking among some of those old, noble trees — a wonderful experience.

Recent research has shown that back to 1900, human activity (anthropogenic) has been influencing drought and moisture across the planet. Scientists involved in the study documented drying soils across the populated North America, Central America, Eurasia and the Mediterranean, while the Indian subcontinent has become wetter. A May 2019 article addressing this research in Earth Institute, Columbia University, State of the Planet provides some details. “They used tree rings going back 600 to 900 years to estimate soil moisture trends before human-produced greenhouse gases started rising, then compared this data with 20th-century tree rings and modern instrumental observations, to see if they could pick out drought patterns matching those predicted by computer models, amid the noise of natural yearly or decadal regional weather variations.”

The results of the scientific work are revealing. “We asked, does the real-world look like what the models tell us to expect?” said study coauthor Benjamin Cook of the NASA Goddard Institute for Space Studies and Columbia University’s Lamont-Doherty Earth Observatory. “The answer is yes. The big thing we learned is that climate change started affecting global patterns of drought in the early 20th century. We expect this pattern to keep emerging as climate change continues.” The fingerprints of humanity seem more and more indelible.

Here’s the one-month weather data for April 2019. All measurements are from my home weather station. The high temperature was 71.8˚F on the 21st; the low was 29.0˚F on the 29th and the mean for April was 51.1˚F. The all-time high temperature was 92˚F in 1936, all-time low was 20˚F in 1936, while the all-time mean is 49.9˚F. Our mean was 1.2˚F higher. Precipitation was 1.02 inches of rainfall. The all-time mean precipitation is 0.86 inches, with an all-time maximum of 2.31 inches back in 1948. Yes, snowfall ended in March — zero white stuff in April.

I’ll close this month’s column with an exercise of the First Amendment. The current federal administration has nominated a fellow named Barry Lee Myers to the post of administrator of the National Oceanic and Atmospheric Administration. NOAA is home to the National Weather Service (NWS). Mr. Myers was the most recent CEO of AccuWeather, a private company that, in part, takes data from the National Weather Service, then reiterates it for profit purposes. That’s all well and good; NWS data is public domain. Myers left the CEO position in January to pursue the NOAA position. However, and this is important, Mr. Myers not so long ago pushed legislation that would have prevented, except in emergencies, the NWS from providing weather information to the public, saying it was unfair competition with his “industry.” The legislation didn’t pass, though it could come around again. It doesn’t take a deep-thinking person to see what will go on within NOAA if or when Mr. Myers is confirmed and becomes the new administrator of NOAA. I’ve tried, though can’t get a weather forecast for the Washington D.C. Swamp.