Supposedly the 1900s and into the 2000s have seen a substantial increase in temperatures, all due of course to human use of fossil fuels. But there might be a few questions about how accurate temperatures are from early in this period, and throughout the period, there are lots of methodological “adjustments” that always seem to increase the recorded temps and/or trend. Land surface temperatures have lots of issues, but two-thirds of Earth’s surface is water and ocean surface temperatures are even more problematic. The historic record tends to be from ships taking measurements as they traveled. Buckets were used to haul up water and then take its temperature. Ship water intakes have also been used. Today there are floats and satelites and other approaches that are more accurate, at least before adjustments.
The authors in this particular study do a rigorous re-examination of the supposed ocean surface temps, focussing on the period in the early 1900s, from around 1900 to 1930. They find that previous measurements and estimates were likely too “cold”. In other words, the ocean surface temperatures were warmer than previously estimated, which is important because it means the trend of warming is much lower than previously calculated. The commentary and article are worth reading, not just because of the implications for climate policy, but because you get a good sense of just how flimsy the temperature record is from more than 50 or 60 years ago and how imprecise older methods of measurement were. Science indeed. A big part of science is acknowledging, highlighting uncertainty and potential error. But not the climate hysterics, oh no, they are just certain we are burning up and it is all due to CO2 produced by fossil fuels. (Nature Article) (Nature Article)
However, NONE of this will register to the acolytes of Global Warming!!