by K. Richard, Sep 21, 2020 in NoTricksZone
Paleoclimate reconstructions that find no unusual modern warming are nonetheless characterized as showing sharp temperature increases in recent decades anyway.
A new (Li et al., 2020) 1818-2012 temperature reconstruction determined 1955 (6.33 °C) and 2001 (7.17 °C) were the 1st and 5th coldest years in northeastern China in the last 200 years. The two warmest years were 1832 (9.63 °C) and 1900 (9.57 °C).
Further, the highest “continuous high decadal temperatures” recorded were in 1818–1844 and 1856–1873. The post-1950s temperatures were colder than nearly all of the first 100 years of the temperature record.
And yet in spite of the warmer 19th-century temperatures, the authors chracterize the slight temperature rise since the 1950s as heralding in “unprecedented” warming. They make this claim (of “unprecedented” recent warmth) in both the paper’s textual and graphical abstracts.
Image Source: Li et al., 2020
Forbes et al. (2020) use thermometer data from an Alaskan airport for the last ~90 years of their temperature record. The instrumentals show surface temperatures cooled -0.7°C in winter (January) and warmed 0.8°C in summer (July) from the 1950s-’80s decades to the 1990s to 2010s.
For the summer temperature record (shown in red below), nearly all the warming occurred during a step-change from the mid-1970s to mid-1980s. Since about 1985, summer temperatures seem to have been stable to slightly declining.
A lack of net overall warming in the last 50 or 60 years does not advance the anthropogenic global warming (AGW) cause, of course.
by Tony Heller, March 5, 2020 in RealClimateScience
Over the past 30 years, NOAA has been rapidly losing US thermometers. In 1989, 1,205 stations reported some daily temperatures, but last year only 871 stations reported some daily temperatures.
Thirty-five percent (424) of the stations in 2019 were zombie stations, meaning that NOAA estimated data for all twelve months. This is done even for some of the thermometers which reported at least a little data in 2019.
by Paul Matthews, June 30, 2019 in ClimateScepticism
The history of climate scientists adjusting data to try to make recent warming look greater than it really is goes back quite a long way – it’s a regular topic at Paul Homewood’s blogfor example. But climate scientists continue to do it, giving the sceptics plenty of ammunition. Here are three recent blog posts discussing how climate scientists continue to adjust data to exaggerate warming.
At Pierre Gosselin’s blog there’s a guest post by Kirje from Japan, on NASA GISS temperature adjustments. In the latest GISS version, V4, the supposedly “unadjusted” data sets are different from the unadjusted data in the previous version V3.
Tony Heller has a graph of the 2000, 2017 and 2019 version of NASA GISTEMP, showing that Gavin Schmidt and his team have managed to crank up warming, particularly in the era of the inconvenient pause. You can also see this effect in fig 2 and fig 4 of the GISS history page.
Here in the UK, the HadCRUT4 team are doing the same thing. Clive Best asks Whatever happened to the Global Warming Hiatus? The answer is that they have demolished it with a sequence of adjustments to the data. HadCRUT3, as published in 2014, shows a clear pause, with no warming from about 2001-2013, but the latest new improved data set HadCRUT4.6 cranks recent temperatures upwards. Clive thought that night be due to including different measurement stations, but checked and found that was not the case. The numbers have simply been adjusted.
Here the red diamond is the raw data, the green diamond is HadSST3, and the new HadSST4 is shown as the black line, with grey shading representing uncertainty. In the early years of the 20th century, there was global warming that doesn’t fit with the carbon-dioxide-controlled theory of climate scientists, so that is adjusted downwards. But look at the trend over the pause era, since 2000. The raw data shows literally no trend at all. HadSST3 adjusted the trend upwards to create warming, and HadSST4 adjusts things upwards again, roughly doubling the previous adjustment. And this is in an era when the data quality should be excellent, thanks to the introduction of the ARGO float system.