JANUARY 16, 2021
By Paul Homewood
There has been a nice discussion on Twitter, regarding the GWPF’s latest bulletin inconveniently pointing out that there has been no global warming in the last 5 years:
But why does Richard Betts show a graph beginning in 1958, which implies that ocean warming suddenly started to accelerate after 1990? True, there is little reliable ocean heat content data prior to 1958, but some would argue that the data prior to ARGO buoys, rolled out in 2004, is also worthless.
Although the graph is labelled in Zettajoules, designed to make it look scary, the actual temperature changes involved are microscopic, and impossible to measure to such accuracy in pre-ARGO days.
Since 2004, for instance, ARGO data shows an increase of about one hundredth of a degree.
But we do have much longer records of sea surface temperatures, for instance the Hadley Centre’s HADSST3:
You will note a couple of things.
First, global sea temperatures actually fell between 1940 and 1980. (This coincided with sea level rise slowing down). Betts, of course, would like you to believe that the accelerating rate of rise since then is due to AGW, rather than a natural cyclical event.
Secondly, sea surface temperatures began rising from 1900, long before CO2 emissions could have had the slightest effect on the world’s climate.
Indeed the rate of rise from 1910 to 1940 was every bit as fast as since 1980. This also correlates with tidal gauge records of sea level rise around the world, which show a similar pattern.
Simple physics tell us that the oceans drive the world’s climate, and not the atmosphere. The heat capacity of the oceans is so much greater than the air, that the heat capacity of an atmospheric column of unit area cross section extending from the ocean surface to the outermost layers of the atmosphere is equivalent to the heat capacity of a column of seawater of 2.6-metre depth.
Put another way, rising ocean temperatures cause atmospheric temperatures to rise, and not vice versa. We can readily see that every time there is an El Nino.
So the real question is what has caused sea temperatures to steadily rise since 1900? And if you think it is greenhouse gases, then you need to explain how these also caused the pre 1940 rise.