A Climate Realist’s (not so) short Answers to Hard Questions About Climate Change. Question 15 (of 16) Will the seas rise evenly across the planet?

NOV. 28, 2015 gave his answers to 16 questions in the N.Y. Times regarding Climate Change. This Climate realist added his answer.

 Answers to Question 1: How much is the planet heating up?

Answers to Question 2. How much trouble are we in?

Answers to Question 3. Is there anything I can do?

Answers to Question 4. What’s the optimistic scenario?

Answers to Question 5. Will reducing meat in my diet help the climate?

Answers to Question 6. What’s the worst-case scenario?

Answers to Question 7. Will a tech breakthrough help us?

Answers to Question 8. How much will the seas rise?

Answers to Question 9. Are the predictions reliable?

Answers to Question 10. Why do people question climate change?

Answers to Question 11. Is crazy weather tied to climate change?

Answers to Question 12. Will anyone benefit from global warming?

Answers to Question 13. Is there any reason for hope?

Answers to Question 14. How does agriculture affect climate change?

Justin Gillis answer to Question 15. Will the seas rise evenly across the planet?

Think lumpy.

Many people imagine the ocean to be like a bathtub, where the water level is consistent all the way around. In fact, the sea is rather lumpy – strong winds and other factors can cause water to pile up in some spots, and to be lower in others.

Also, the huge ice sheets in Greenland and Antarctica exert a gravitational pull on the sea, drawing water toward them. As they melt, sea levels in their vicinity will fall as the water gets redistributed to distant areas.

How the rising ocean affects particular parts of the world will therefore depend on which ice sheet melts fastest, how winds and currents shift, and other related factors. On top of all that, some coastal areas are sinking as the sea rises, so they get a double whammy.

My answer to Question 15. Will the seas rise evenly across the planet?

We are still recovering from the last ice age. The planet is becoming less ovoid, more like a sphere. In the Bothnian Bay land is rising out of the ocean at a rate of about 3 feet per century. It is by no means over yet. The displaced water gets redistributed over the rest of the earth. In addition the Mid-Atlantic ridge is expanding and rising with numerous undersea volcanoes, maybe up to one third of all undersea volcanoes are located between Jan Mayen and Svalbard. Teutonic plate movements explain the rest. The Eastern Seaboard is slowly sinking into the sea, more than the rest of the world. Te expansion of the ocean is not accelerating.The take home from this picture is that there are cyclical factors quite apart from rising CO2, but sea level rise is not accelerating.

Answers to Question 16. Is it really all about carbon?

A Climate Realist’s (not so) short Answers to Hard Questions About Climate Change. Question 8 (of 16) How much will the seas rise?

NOV. 28, 2015 gave his answers to 16 questions in the N.Y. Times regarding Climate Change. This Climate realist added his answer.

 Answers to Question 1: How much is the planet heating up?

Answers to Question 2. How much trouble are we in?

Answers to Question 3. Is there anything I can do?

Answers to Question 4. What’s the optimistic scenario?

Answers to Question 5. Will reducing meat in my diet help the climate?

Answers to Question 6. What’s the worst-case scenario?

Answers to Question 7. Will a tech breakthrough help us?

Justin Gillis answer to Question 8. How much will the seas rise?

“The real question is not how high, but how fast.

The ocean is rising at a rate of about a foot per century. That causes severe effects on coastlines, forcing governments and property owners to spend tens of billions of dollars fighting erosion. But if that rate continued, it would probably be manageable, experts say.

The risk is that the rate will accelerate markedly. If emissions continue unchecked, then the temperature at the Earth’s surface could soon resemble a past epoch called the Pliocene, when a great deal of ice melted and the ocean rose by something like 80 feet compared to today. A recent study found that burning all the fossil fuels in the ground would fully melt the polar ice sheets, raising the sea level by more than 160 feet over an unknown period.

With all of that said, the crucial issue is probably not how much the oceans are going to rise, but how fast. And on that point, scientists are pretty much flying blind. Their best information comes from studying Earth’s history, and it suggests that the rate can on occasion hit a foot per decade, which can probably be thought of as the worst-case scenario. A rate even half that would force rapid retreat from the coasts and, some experts think, throw human society into crisis. Even if the rise is much slower, many of the world’s great cities will flood eventually. Studies suggest that big cuts in emissions could slow the rise, buying crucial time for society to adapt to an altered coastline.”

My answer to Question 8. How much will the seas rise?

During the Pliocene epoch the water levels were about 80 feet higher than today, temperatures were 1 to 3 degree C warmer, but the CO2 level was less than 280 ppm, so there must have been another cause for the high temperatures than Carbon dioxide. My guess is that the activity of the Sun and the Milankovitch cycles triggered the meltdown of most of the Greenland and part of the Antarctic ice sheet. This is not the case now.  We are well into the bog generating phase of this interglacial period, the Minoan optimum temperature ( at 260 ppm CO2) did not trigger the ice-melt, and ever since we have been in a downward temperature trend. What is remarkable about this period is how stable sea levels have been. The ocean levels have been rising at an average rate of about one inch per century, quite different from emptying out the Baltic Ice Lake, an event that rose  Ocean levels by feet per year until it emptied out, the rest formed what is now the Baltic Sea. Coming out of the ice age rose Ocean levels about 400 feet, and then it stopped. There are places in northern Sweden where the land still rises out of the sea at about 3 feet per century. The Mid-Atlantic ridge is rising, has plenty of undersea volcanoes, about one third of all undersea volcanoes are between Jan Mayen and Svalbard. All this displaced water has to go somewhere, and so most of the rest of the world’s coastlines are experiencing rising sea levels. This is especially true for the U.S. East coast, sinking of its own. The warming of the oceans are vastly over-estimated, being confined to the surface and the upper 1000 feet, the sunlight is absorbed in the first few feet of water and there is limited and very slow mixing of deep water with surface water. But there is a temperature dependence of sea levels, the sea levels were fluctuating with temperature, as the chart to the right indicates.

Right now average ocean levels are increasing by about a foot per century, but the trend is not increasing. See Fig:

The take-home from this chart: Sea level rise has nothing to do with CO2 level rise, it is more about tectonic plates movements and what happens on the sea floor.