A long-awaited document was released last week by the National Oceanic and Atmospheric Administration/NOAA administered U.S. Global Change Research Program. This is one of the most encyclopedic compendiums of its kind, and it was issued despite some indications of hostility toward its findings by the current administration. The research project has roots which precede this presidency, and could not readily be snuffed out if that were anyone’s intention in the administration due to approved funding and congressional mandate.
Climate Matters, a private organization in Princeton, saved me the trouble of reading the entire exhaustive report, but here are the top 10 findings within this first volume:
- The global average temperature has increased 1.8°F (1°C) from 1901 to 2016, and is rising faster that at any time in the last 1,700 years.
- The average annual temperature over the contiguous U.S. has increased 1.8°F from 1901 to 2016. Surface and satellite data are consistent in their depiction of rapid warming since 1979. With no change in the rate of greenhouse gas emissions, an additional 5.8 to 11.9°F increase is projected by 2100.
- There have been marked changes in temperature extremes across the contiguous U.S. The number of high temperature records far exceeds the number of low temperature records. This trend is projected to continue.
- The global influence of natural variability is limited to a small fraction of observed climate trends. Solar output changes and internal natural variability can only contribute marginally to the observed changes in climate over the last century, and there is no convincing evidence for natural cycles in the observational record that could explain the observed changes in climate.
- Heavy precipitation events in most parts of the U.S. have increased in frequency and intensity since 1901, with the largest increase is in the Northeast and the second largest increase in the Midwest.
- Northern Hemisphere spring snow cover, North American maximum snow depth, and Western snow water equivalent have all declined.
- Global mean sea level has risen about 7-8 inches since 1900, with about 3 of those inches occurring since 1993.
- The world’s oceans have absorbed 93 percent of the excess heat caused by global warming since the mid-20th century. Oceans are warming, rising, and getting more acidic.
- The Arctic is warming at a rate approximately twice as fast as the global average and, if it continues to warm at the same rate, Septembers will be nearly ice-free in the Arctic Ocean by the 2040s.
- For Atlantic hurricanes, increases are projected in precipitation rates and intensity.
Item 4 is an especially key finding, and I’ve written of this in past articles. There is overwhelming evidence human activity is responsible for the ongoing average global warming, and no real evidence of natural warming would be occurring without our activity and the increase in the atmosphere’s greenhouse effect linked to that activity. In fact, at an American Meteorological Society conference held in the National Center for Atmospheric Research, climate scientists demonstrated to me and many colleagues climate models initialized with the carbon dioxide levels we had around the year 1900, even with natural warming agents such as solar forcing maxed up, demonstrate the world would have been slightly cooling since 1900. There is no explanation for the warming other than “us” and what we have added to the air.
It’s the ocean which has been the great modifier in slowing atmospheric warming because it is a heat “sink.” It absorbs excess heat and carbon … up to a point.
Sea level rise is inexorable, due to freshwater ice meltoff from Greenland, Antarctica and glaciers, and due to expansion from warming waters.
Rutgers University’s Global Snow Lab tracks the northern hemisphere’s snow cover and shows a distinct downward trend for North America.
The hotter environment has led to more wildfires out west, as was the case this autumn.
As accurately modeled by climate scientists decades ago, warming has led to more evaporation and more water vapor in the air to produce more extreme rainfall events. Each degree increase in the global average temperature adds an additional 4 percent water vapor into the atmosphere, the latter also being a greenhouse gas.
Even in Buffalo, where we have our great modifier Lake Erie in place, we have seen an increase in daytime heating. Nightime lows, not depicted here, have risen even more because we lose the modifying lake breeze most nights.
Buffalo’s average summer temperatures have risen as well.
Finally, our annual average temperature has risen too.
The temperature data in this and other studies is carefully controlled for quality and uniformity. In other words, no one is using readings taken in Times Square to be representative of southeast New York. Every effort is made to scrub out as much of the urban heat island effect from regional, national, and global temperatures in the database as possible.
The climate models which began to proliferate numerically and dramatically improve in quality during the 1980s have done pretty well, with more warming impacts being slightly greater in scope than lesser. They should never be confused with meteorological models, because climate models are designed to filter out the “noise” of day-to-day fluctuations and operate on a smoothed timescale.
So, the notion “we/meteorologists have trouble with a seventh day in the 7-day outlook, so why should anyone believe climate predictions a century out?” is a red herring and irrelevant. For those of you who are REALLY ambitious and have lots of time, here is the link to this entire volume. The volume can serve as an excellent resource and is worth bookmarking.