“…a distinct pattern of water vapor suppressing the [sea surface temperature] diurnal amplitudes at low latitudes” – Harris et al., 2025
Observations show morning-to-evening sea surface warming amplitudes can exceed 5°C.
Water vapor (WV), the greenhouse gas (GHG) mostly responsible for Earth’s greenhouse effect, adds ~0.1°C warming to this 5°C diurnal change in the high latitude oceans, where WV concentrations are only 100-1000 ppm.
In the tropics, where its concentrations reach 40,000 ppm, the WV contribution to this >5°C diurnal warming is flat (~0.0°C) to negative (a -0.2 to -0.3°C cooling effect).
A 40-fold increase in GHGs/WV can thus can be shown to contribute to cooling the ocean surface instead of enhancing warming.
This is the opposite of what would expected to occur if increasing GHGs were indeed responsible for warming the global oceans.
I have this friend. Each year or so he gets frantic when visiting that Bangladesh is being swamped by ahem global warming even as nothing changes. Except the silting of rivers which is being ignored to contribute to local floods. I send him the occasional articles like this one without comment. Its up to him to decide not me. I got over the panic attacks after reading the history of how Greenpeace fell into the clutches of the extremists and science became an inconvenient abstraction to misquote some politician. Most people know that water vapour content decides how hot it gets. Thus the temperature in the tropics is worse than in the dry desert. This however is even better. Stunning result.