By Paul H. Reitan
Q: Why all the fuss? All they’re talking about is a few degrees warmer in a hundred years. So why are the Intergovernmental Panel on Climate Change (IPCC) and Al Gore making such a big issue of it? After all, the temperature change from morning to afternoon or from winter to summer is a LOT more. And a few degrees in a hundred years – why, that’s only a few hundredths of a degree per year!
A: It’s easy to see why the amount of heating of the Earth doesn’t seem like much and the rate seems very, very slow – especially when compared with all of the other changes buzzing around us. But some perspective may help to understand why the few degrees the IPCC projects over a hundred years really is a big deal.
We all know about the Ice Ages, when huge ice sheets spread southward. Those ice sheets were so large that here, where Buffalo now exists, the ice was a mile thick. In recent decades it has become possible to determine the average global temperature when glaciers were that big, and the change of temperature throughout several Ice Age glacial and interglacial periods. But let’s just consider the time from the end of the last glacial period and the transition into the beginning of our present interglacial. At the time of the maximum extent of the ice sheets with the deepest cold, about 14,000 years ago, the average global temperature was about 5 degrees Celsius (9 degrees F) colder than it was 200 years ago – about when human-caused warming began. Then, over the next 5,000 years the Earth temperature increased about 5 degrees C. About 9,000 years ago Earth temperature stabilized and the temperature has varied only a little since then. The change from the coldest time with maximum glaciation to recent Earth temperature was only 5 degrees C and it happened over about 5000 years. A change of one degree per thousand years. But that was enough to change our world from a glaciated world to what it is today.
But if, for example, Earth’s average temperature were to increase an additional 3 ½ degrees C by 2100, we will have had a temperature increase above the past 9000 year average of more than 4 degrees C from the beginning of the Industrial Revolution, with the beginning of intensive burning of fossil fuels, to 2100.
Another way of putting it: during the 21st century Earth’s temperature would increase about 35 times faster than it did as the last Ice Age glaciation ended, and that change was extremely fast by natural standards.
Q: OK, we are anticipating a temperature increase that will be very big and very rapid as compared with natural rates of change. So what? Why worry?
A: As the last major glaciation ended and climate changed, Earth’s ecosystems responded. As the ice front retreated ecosystems migrated northward. At the latitude of Buffalo the climax forest is now one of oak, maple, and beech. 14000 years ago those trees existed in refuges down in Georgia. But with climate change the forests marched northward – slowly, but keeping up with what climate allowed. With temperature changing a degree per thousand years ecosystems could keep up, they could adjust and adapt.
But a temperature change of a few degrees in a hundred years? We have every reason to expect that will be too fast for many species. Some species are mobile and may move quickly, but many are not. Forests, for example, do not migrate quickly (the lifespan of many trees is well over 100 years). So we must expect many species and ecosystems to become extinct; some species will try to move but much of their ecosystem will not keep up, and the synchronization and interdependence that characterizes ecosystems will be disrupted. Result: ecosystem failures both on land and in the sea.
We might be able to build dikes and move our societies in response to sea level rise. But we are not able to construct ecosystems, even though we depend upon them.
The only prudent choice we have is to make the changes needed in how our societies live so that we minimize global heating. Are we able to be farsighted? Is that possible?
As Al Gore said in his Nobel Peace Prize acceptance speech in Oslo, Norway, on December 10, 2007, “We have everything we need to get started, save perhaps political will ….”.
February 6, 2008 at 9:51 am
What if they are all full of crap? What if they cooked up this hoax to institute a Global Tax on carbon to control the economic development of the World while bankrupting the middle class while limiting personal freedoms, while they use the carbon tax money to create a World Government with the goal of reducing human populations by 80%?
How long will it take to admit that you are wrong about Global Warming? How low do temperatures have to go to prove that this is nothing but a hoax? How long do temperatures have to remain the same?
Is there anything that can disprove climate change? Now they are saying that cold weather means climate change too?
Why do the high priests of Global Warming refuse to debate? Then claim that the debate is over?
After filtering out the effects of a warm PDO, which coincided with a warm AMO, an unusually short solar cycle do they determine how much of the Global Warming effect is man made?
Given the fact that the current solar cycle is currently 13 months late, and may not arrive for another 20 months, and given the fact that for every day its late has an historical trend of coinciding with a 1.4/1,000th of a degree C decline in Global Temperature, and the fact that the PDO has entered a cool trend, and we have a strong La Nina. How are the high Priest of Global Warming going to hide the fact that its getting much cooler outside?
Should Scientists, politicians and members of the media who have acted so recklessly with our national assets and propagated a world wide panic which is already having adverse economic and environmental effects be prosecuted legally? Should they at least be fired?
February 9, 2008 at 12:52 am
Johhnyb asks if global warming might just be a hoax. Could it be?
If it is, it is the most elaborately orchestrated international conspiracy to misrepresent and misinform ever concocted. It would represent the secret collusion of serious professionals around the world deciding to put their professional integrity and careers on the line for no conceivable benefit to themselves. Further, the global climate scientists of the world would never ever be in a position to “… control the economic development of the World while bankrupting the middle class …”, which, by the way, is the class to which they belong. But the short answer to “Is it a hoax?” is: “No. All of the members of the world’s scientific community have not all simultaneously gone mad.”
I recognized comments that seemed to express observations Johnnyb thought were not consistent with global warming.
I’m not surprised that Johnnyb thinks cold weather can’t be associated with climate change that accompanies global warming. It may seem strange, but it’s not a surprise. If we trap more energy in the lower atmosphere we should expect more energetic weather and more energy able to pull cold polar air down to mid-latitudes. Energy to set up conditions for the kind of extreme weather – mid-winter tornadoes – that just caused deaths and so much damage in Arkansas and Tennessee.
Then there’s the question, is the debate about global warming over?
No, it’s not. There are deniers of reality who may never know when to quit. But among those who have followed the research over the last 30 years and those who are willing to take the world’s community of climate scientists seriously (and who don’t think they’ve all suddenly lost their minds) and those who care to believe in measured data, there isn’t any debate about anthropogenically caused global average temperature increase over the last 250 years – and especially in the last 50 years.
Johnnyb seemed to suggest some kind of relationship to the solar cycle, and there is. But since 1750 the measured increase in CO2 has caused almost 14 times as much warming as that attributable to the change in solar irradiance, and together with the other greenhouse gases, methane, halocarbons, and oxides of nitrogen, about 22 times more warming than that from the change in solar irradiance. Even the absorption of solar energy by soot that darkens otherwise reflective surfaces, such as snow, has caused about twice as much warming as that by increased solar irradiance over that time period. The sun keeps us warm, but we are causing the sun’s warmth to be held in much greater degree than the sun is increasing the warmth it sends to us.
Finally, Johnnyb, if it’s your pocket book that worries you and the “adverse” economic effects you see resulting from information about the warming and climate changes that have already taken place and the warnings about future warming and its impacts, then think about the economic opportunities associated with significant increases in energy efficiency and the development of innovative, flexible, non-polluting energy sources. Think of them as an alternative stimulus to our economy and use of our wealth each time we decide to buy a $300 million F22 fighter plane.