Wood Romances

There's a very strange conspiracy theory that has been floating around social media since 2017 that an ex-NOAA employee became a "whistleblower" to alert the world of fraud in NOAA's GMST dataset. It's a strange conspiracy theory because even the so-called "whistle blower" says that the conspiracy theorists are wrong. Let's set the context. A paper was published in Science in 2015 (the "Karl study") arguing, “Here, we present an updated global surface temperature analysis that reveals that global trends are higher than those reported by the Intergovernmental Panel on Climate Change, especially in recent decades, and that the central estimate for the rate of warming during the first 15 years of the 21st century is at least as great as the last half of the 20th century.” Dr. John Bates in 2017 decided to go public with complaints about NOAA's process in 2017 (after retiring in November 2016). To be clear, Bates said nothing publicly about...

Recently NOAA released v. 5.1 of their global GMST dataset and, aside from adding full global coverage, it extended the dataset back to 1850. This gives us a third GMST dataset that goes back to 1850. Since the IPCC uses the 1850-1900 mean as a baseline to represent "preindustrial" temperatures, this gives us three datasets to use to calculate the amount of warming we've experienced above preindustrial levels. The IPCC has set a target of +1.5°C above preindustrial temperatures, where +1.5°C is a 30-year average above the 1850-1900 mean. The IPCC estimates that 2011-2020 averaged +1.1°C above preindustrial levels. But the question I have is, where are we now, and when will we cross the +1.5°C and +2.0°C targets if we continue warming at current rates? To answer this question, I took the data I've already downloaded from NOAA (monthly), HadCRUT5 (monthly) and Berkeley Earth (annual). The NOAA dataset is current through January 2023 and the other two are current through...

Virtually all temperature datasets that have been around for a significant amount of time depend on surface thermometers, most of which were not designed to measure climate changes; they were positioned to collect meteorological data for temperature and precipitation, and many of these stations have been maintained by volunteers. In earlier years there was no standardized process for even when temperatures were recorded. Daily temperatures were calculated using max-min thermometers that recorded the "max" and "min" temperatures recorded by the thermometer since the last time it was checked and reset. If the thermometer was checked daily, this would give data for daily highs and lows. The average temperature for the data as calculated simply by Tavg = (Tmax + Tmin)/2. Biases can easily enter into the temperature record by systematic changes in 1) time of observation , 2) instrument technology, and 3) urbanization, as well as other factors. Likewise, sea surface tempe...

Within the last week or so, NOAA issued an update to their Global Mean Surface Temperature dataset. The update to v. 5.1 now has full global coverage (mostly due to increased coverage of the Arctic) and extends back to 1850. The results are pretty close to to the v. 5 dataset, and I suspect differences in trends between the two will not be significant over time frames of 30 years or longer. Below I plotted v. 5 and v. 5.1 with the difference between the two (v.5.1 - v.5). The changes are minimal and there is virtually no trend to the difference. The additional warming in recent years is likely due to the increased Arctic coverage . I also found the global raw data (with no adjustments or bias correction) and plotted v. 5 and v 5.1 so that you can see the effect of bias correction on global temperatures. The largest adjustments occur before 1944, and they are dominated by increasing sea surface temperatures to account for changes in the sampling methods from ships. Contrary to the clai...