OCTOBER 8, 2020tags: california
By Paul Homewood
I have often published official graphs of individual stations, which show that heatwaves in California were more intense in the past. These run contra to NOAA’s official temperature record shown above.
NOAA themselves, however, a summary of climate trends in California a few years ago, which backs up my station data:
Below is the relevant table:
Not only do the 1930s stand out for heatwaves, but the last decade appears to be little different some of the other periods in between.
The exercise only takes us up to 2014, but my analysis does not suggest anything untoward happening in the last five years. If heatwaves really are getting worse because of global warming, we would surely have seen a steady trend upwards in the number of extremely hot days during the last several decades.
We can compare this state graph with a similar one for Lemon Cove showing number of days over 100F:
The pattern is similar, with heatwaves peaking in the 1930s, followed by a much colder interlude between the 1960s and 80s.
The two years of 2017 and 2018 stand out, but other than that heatwaves at Lemon Cove since 2000 appear to have been around 1940s and 50s levels.
NOAA’s maximum temperature graph is obviously averaged over the whole of the summer, so won’t necessarily reflect the heatwave patterns, It may be that there a fewer unusually cold summer days now, unlikely though that may seem.
NOAA’s graph of extremely hot days does however pose more questions about the reliability and accuracy of their monthly temperature records, both for California and the US as a whole.