https://quadrant.org.au/opinion/doomed-planet/2020/01/alarmed-and-dangerous/
Can we all agree that it is getting hotter? Facts matter and there is no point in agreeing on something that is wrong. However, the evidence seems clear to me. We now have 41 years of satellite data. I think we can rely on Roy Spencer and John Christy at the University of Alabama in ensuring that the NASA satellite measuring program under their purview is throwing up honest data.
That data from the end of 1978 until the end of 2019 shows a trend warming of 0.013 degrees per year; in total 0.54 degrees over the forty-one years. At this rate the temperature would rise by 1.33 over a century. This would represent an acceleration in warming when compared with HADCRUT 4 data (land and ocean) which shows a trend of just 0.90 degrees over the whole period from 1850 to the near end of 2019.
But a degree of caution is warranted in saying that the last forty-one years is a guide to the future. I looked at the forty-one years from the end of 1899 to the end of 1940 (when the global temperature had a local peak) and found using HADRUT data that the temperature had risen by 0.40 degrees. This provided no guide at all to the next forty-one years, when the recorded temperature actually fell by 0.17 degrees. At the same time, to be clear, ‘up’ is the dominant theme since 1850.
Why there is warming is a separate question. Some look to the activity of the sun. I don’t know, I haven’t read anything convincing. Are the larger conglomerations of cities having heat-island effects? I assume so. A scientist friend of mine hypothesizes that world-wide large-scale irrigation may be contributing to water vapor in the atmosphere and thus may be part of the explanation. Again, I don’t know – which is what I would like a lot more people, more qualified than I, to be saying rather than stymieing debate by pretending that everything is certain and settled.