About those rising Global Sea Levels
Here is another common sense (and scientific) reason why the nonsense that NASA tells you about anticipated global sea level rise is nonsense.
First, both NASA and IPCC tell you that increase in Global Sea Levels (GSL) will come about half from "volumetric expansion of water" and half from water melting from glaciers.
Let's take glaciers first. For a 2 C or 3 C increase in average global temperature to make a big difference in melting of ice in Antarctica and Greenland (all the rest of ice is irrelevant), major portions of Greenland and Antarctica would have to be very close to average temperature of 0 C all year round. Because water melts at over Zero C. If on the South Pole temperature "warms up" from -30 to even - 20 all year long, that will not result in any melting ice whatsoever.
Therefore, the relevant areas of ice melt are only on the fringes of both Greenland and Antarctica which in terms of volume of ice account for a truly minuscule portion of overall ice mass. The average height of ice in Antarctica is 1.9 km. Which means in the middle of it, the ice depth is as high or higher as the Alps in Europe or the Rockies in North America. So imagine a sheet of ice the height of Mt. Blanc gradually sloping towards the shores of Normandy. Where ice meets the sea, it is much less thick - from 100 meters to a few hundred meters. So loss of "ice cover" there means much less in volume than it would mean 100 km inland into the Antarctic continent. Over 95% of Antarctica has average annual temperatures below -20 C. Nothing ever melts there unless on a stove. Average annual temperature for the "coast" is -10 C. So even if things warmed up by 5 C in the next 100 years, for vast majority of Antarctica this would make no difference at all in volume of ice melting.
Greenland is in many respects similar and most of it experiences no ice melt other than where the ice touches the sea. And Greenland as a whole is only 9% of all ice on Earth while Antarctica is 90%.
So this notion that there is "tipping point" at some level between 2 C and 4 C warmer than now, when it comes to ice melting and therefore global sea levels dramatically rising is pretty much bogus. Nobody has shown calculations which correspond to observed reality that would show this happening.
And the "thermal expansion" part is no less murky. Water happens to be a substance which has its smallest volume at 4 C. This means that volume of water DECREASES as it warms up from 1 C to 4 C. How much of the water in the world is at that temperature range? I don't know but nobody else does either. And adjustments that have to be made to assumptions of volumetric expansion are massive too. When moon's gravity makes tides emerge that are meters in height, we are supposed to think that calculations of volumetric expansion can be accurate in millimeters? I am not convinced.
Another part of it that temperatures at the surface change quite a bit but temperature changes in deep ocean are small or non existent. And 90% of all volume of water in oceans is in deep ocean where average temperature is 0-3 C and probably has been that for a few million years.
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