Thread by @ncdave4life

@RARohde @wennbergcaltech 1/8》The temperature changes in question are so miniscule they're hard to measure, hence the inconsistencies.

An advantage of satellite temp measurements is their near-global coverage. They measure lower troposphere air temperatures by consistent means, over both land & ocean.

@RARohde @wennbergcaltech 2/8》"Surface temperatures" conflate two quite different kinds of measurements:

1. AIR temperatures, measured in instrument enclosures 1.25-2.0 meters above the ground.

2. Sea-surface WATER temperatures, at varying near-surface depths.

@RARohde @wennbergcaltech 3/8》The best satellite dataset is UAH 6. They're the scientists who pioneered & refined the methods that RSS uses. Here's why UAH is better than RSS:

drroyspencer.com/2019/04/uah-rs…

@RARohde @wennbergcaltech 4/8》A disadvantage of the satellite data is its starting point, in chilly 1979. That's effectively an accidental cherry-pick. It causes the satellite measurements (even UAH) to exaggerate the long-term warming trend.

sealevel.info/ipcc_far_pp224…

@RARohde @wennbergcaltech 5/8》"Surface temperatures" measured over land have quality issues, as proven by the quite radical and often dubious revisions to the "measured" temperatures. E.g., still-unexplained changes erased 0.434°C of cooling from U.S. "raw" temperature data:

sealevel.info/fig1x_1999_hig…

@RARohde @wennbergcaltech 6/8》Surface temperatures over the other 70% of the Earth are even worse!

Before Argo buoys, water temps were mostly taken at ship engine coolant intakes (which vary in depth depending on ship sizes and how heavily loaded the ships are). Before that, they just dipped buckets.

@RARohde @wennbergcaltech 7/8》Worse yet, some of the leading people working with that data, to create those global temperature indices, have squandered their credibility.

sealevel.info/FOIA/125410833…

sealevel.info/wigley_1940s_w…