Friday, January 27, 2023

Colin Summerhayes's "The Icy Planet"

Colin Summerhayes is a chartered geologist and Emeritus Associate for the Scott Polar Research Institute at Cambridge University. He previously served as Executive Director of the International Council for Science's Scientific Committee on Antarctic Research at the Scott Polar Research Institute. His most recent publications include Paleoclimatology (2020) and Earth's Climate Evolution (2015).

Summerhayes applied the "Page 99 Test" to his new book, The Icy Planet: Saving Earth's Refrigerator, and reported the following:
Page 99 talks about making scientific measurements of the atmosphere in East Antarctica, which is the largest ice cube on the planet. What meteorologists need to know to make weather forecasts, aside from the temperature and humidity of the air at ground level, is the profile of these properties up through the atmosphere, which they measure by releasing weather balloons that collect the data and send it back to base via tiny radios. They can also watch how the balloons move sideways with the winds at different altitudes, which indicates wind speed and direction. These measurements also tell us why Antarctica is much colder than the Arctic. You may be surprised to learn that the overlying air is much thinner in the Antarctic, so traps less outgoing heat, thus making this environment cooler than the Arctic. Antarctica also contains a much larger area of ice, which reflects solar energy, which also makes the region colder. And East Antarctica is also higher than the Arctic, averaging a height of 3000 m, which makes it colder. The air at both poles is extremely dry because cold air holds less moisture. And they are also cold because the Sun’s rays are oblique in the polar regions, which means they get much less of the Sun’s energy than the tropics do.

The page 99 text doesn’t tell the reader all about the book, which follows a virtual tour through the world’s icy places – Antarctica, the Arctic, and the world’s high mountain ranges and plateaus, which make up what’s called the Third Pole. The book explains what is happening to the ice, snow and frozen ground (permafrost) in each of these places, demonstrating that we are losing a great deal of the planet’s ice and snow cover. Why does that matter? Well, ice and snow reflect the Sun’s energy back to outer space. That helps to keep our planetary climate moderately cool. As ice and snow melt, the newly exposed ground and sea absorb the Sun’s energy, which warms the surface, which then radiates heat back into the atmosphere. Unlike solar energy, which is not absorbed by greenhouse gases like carbon dioxide or methane, this heat is in the form of infra-red radiation, which those gases absorb and re-radiate, warming the atmosphere. So our climate gets a double whammy: warming due to the emission of carbon dioxide and methane, plus additional warming caused by the loss of our reflective cover of ice and snow. In effect ice and snow act as Earth’s Refrigerator. If you go on vacation and leave your fridge and freezer door open by accident, its contents will rot and melt. So for much the same reason we don’t want to lose any more of Earth’s Refrigerator. And yet all of the data show that the Arctic, the Antarctic and the Third Pole are losing progressively more ice as time goes by. Indeed, the January 2023 issue of Science magazine suggests we will have lost 50% of all the Earth’s glaciers by the end of the century. Imagine that!

Almost everyone knows that melting ice and snow raise sea level. Careful calculations show that our sea level is rising at progressively increasing rates as our climate warms. These same calculations suggest that by the end of this century sea level will have risen by between 1 and 2 metres. But the rise will not stop there. By studying past climates we know that some 3 million years ago when there was a similar amount of carbon dioxide in the atmosphere, sea levels rose by an average of about 15 metres. Are we heading for the same outcome over the next 200 years? Many climate scientists are convinced that we are. This is because the current forecast for the average global temperature by 2050 is 2.7 degrees Centigrade, well above the UN’s guardrails of between 1.5 and 2.0 degrees. These averages conceal something important – the temperatures in polar regions tend to be about three times higher than the global average. So, 2.7 degrees globally would translate to 8.1 degrees Centigrade in, say, the Arctic, which means a lot more ice and snow melt, which means yet more global warming, and yet more sea level rise.

The key question, then, as we face this threat, is what can be done about it? Some people blame the rise in global population, but matters are seldom so simple. In fact it is abundantly clear that the problem is not population, it is consumption. The richest 10% of the population causes 50% of the greenhouse gas emissions. The richest 1% causes 14% of global greenhouse gas emissions, which is double the emissions of the poorest 50% of humanity. This is primarily a problem of excessive consumption by western countries, and demands a primarily western solution. Do our leaders realise this? Many people are calling for a techno-fix, but currently none of the technologies on offer can match the size of the challenge. Governments and industries must work together urgently to fix this, if our grandchildren are to live in a climate like the one we grew up in. Unfortunately, as Greta Thunberg points out in The Climate Book (2022) one of our key problems is that “we are not aware of the fact that we are not aware” when it comes to understanding the climate crisis and the urgent need to act. Even so, The Icy Planet ends on an optimistic note. Provided people are prepared to accept the need for change, then change we can.
Learn more about The Icy Planet at the Oxford University Press website.

--Marshal Zeringue