Earth is warmer now than in the late 1970s, the start of the satellite era.
This can be explained largely to the turn of the Pacific and the Atlantic to their warm cycles. This is the “Bathroom Shower Theory” that I have used many times. Turn on a hot shower, and the bathroom will heat up until an equilibrium is reached. When the Pacific warmed, and the Atlantic followed, we came off a period in which they were cold in tandem. It is perfectly logical that with the oceans and especially the tropics — the thermostat for the globe — warming, the air has to warm until it reaches an equilibrium, which it appears to have done overall until the last 20 years when it has not warmed.
The recent El Niño spike has already started to descend. Given that dry cold air is easier to warm than already warm moist air, the natural place the warming shows up most is where the atmosphere is driest and coldest. The biggest warming has been in the Arctic during winter. Recent summers in the region have actually been a bit below normal. There is no argument here. The question is how much of this is because of the increase of greenhouse gases, specifically CO2.
Another question: Will temperature measurements return to where they were back in the late ‘70s?
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