Climate change. Haven’t we heard it all? Why doesn’t it just go away? Well, no, we haven’t and it won’t. And anybody who cares to pass on a livable world to his grandchildren should be paying attention.
There Appears To Be An Argument Where There is None
The earth emits radiation in the microwave region of the electromagnetic spectrum (wavelengths around ten million angstroms). This outgoing radiation balances the radiation that comes in from the sun. The sun’s radiation is mainly in the visible part of the spectrum (wavelengths around five thousand angstroms). Carbon dioxide and other greenhouse gases in the air absorb microwave radiation, but are transparent to visible light. Only a hardline science-denier would deny that increasing greenhouse gases would have any other effect than to warm the atmosphere. Feedback mechanisms could alter the course of the warming, and possibly the feedback could exactly balance the effect of the increase in greenhouse gases. But the chances of this are slim (actually closer to none).
Climate-Change-Denier Claim #1: It Was 80 Below Zero in Alaska Last Winter.
Completely false. In fact, there has never been a valid measurement of a temperature of minus 80 in Alaska. The coldest on record is minus 79.8 and that was recorded in 1973. Last year’s alleged reading was made with a thermometer that was rated to be reliable down to minus fifty. Below that temperature it is wildly inaccurate. The fact is that temperatures are rising rapidly at high latitudes.
And What if It Had Been True?
One of the manifestations of climate change appears to be a tendency to more extreme weather. Record cold is actually consistent with most of the theories of how the climate will change. This brutally cold winter in the north-central United States is a good example. Anyone living there would think we’re going into another ice age. But the average temperature worldwide for the months December through February are close to the warmest on record.
Climate-Change-Denier Claim #2: The Temperature Hasn’t Changed in 15 Years.
This claim is based on the anomalously warm year of 1988, a year with a powerful El Nino which heated the tropical Pacific and the overlying atmosphere. First figures showed that 2013 was slightly cooler than 1988. However, recent analyses which incorporate better polar data show that even this comparison is wrong. In addition, when the data are smoothed over several years, it is clear that the warming trend continues. Most recently, November and December of 2113 and January of 2014 were warmer than their counterparts fifteen years ago.
And What if It Had Been True?
Suppose the temperature had leveled off for the last fifteen years. To be sanguine about it strikes me as being similar to the cavalier attitude of a parent whose child has slid from an A to a D, but has recorded consecutive terms of D. Not to worry, the slide has been arrested. The temperature of the earth has leveled off, so everything is hunky-dory. Except it hasn’t and it’s not.
Where Does the Heat Go?
More complete analyses of the earth-ocean-atmosphere system indicate that if one includes the heat captured in deeper layers of the ocean, global warming continues unabated. Which is not a surprise. Cars, factories, power plants, and outdoor grills continue to spew greenhouse gases at a high, though perhaps less rapidly increasing, rate. Developed countries have reduced emissions marginally; but the increased emissions from developing nations overwhelms this decline. The simple fact of the physics of gases remains: Greenhouse gases trap microwave radiation. The sun’s output is constant to a tiny fraction of a percent. Ergo, heat is increasingly being trapped by the earth-ocean-atmosphere system.
Is There Hope of Reversing the Trend?
The short answer is no. This is a political question, with historical polluters pitted against modern ones. Countries with high per capita greenhouse gas emissions do not want to give up their lavish lifestyles, while developing countries want to improve theirs. The burgeoning number of coal-fired power plants in China overwhelms the nominal decrease in emissions of the world’s biggest per capita polluter, The United States.
What’s the Bottom Line?
Basically, you ain’t seen nothin’ yet. The trajectory has been established; heat is building up in the earth-atmosphere-ocean system; humanity, unwilling to stop producing greenhouse gases, is unable to stem the tide — literally and figuratively. No one can be certain, or even moderately confident, what the end result will be. But here are some of the preliminary indications.
- The Arctic region has shown the most alarming warming. The temperature on virtually every winter day for the last fifteen years has been well above the long-term average. The feedback of this is positive. Water absorbs solar radiation while ice reflects it. As a result, an ice-free Arctic Ocean will absorb radiation and exacerbate the warming.
- Globally, the most important feedback mechanism of warmer temperatures is more moisture in the air (warm air holds more water vapor than cold). The feedback here is negative: more moisture means more clouds, and clouds reflect solar radiation. Overall, rainfall will increase, but the changes in the distribution of precipitation are unknown. Disruptions to agriculture are certain; some are already occurring.
- Polar and glacial ice is melting and sea level is rising at an increasingly alarming rate. After a rise in sea level of a foot in the last century, projections show oceans rising as much as five feet in the next 100 years. Coastal cities will have to either armor or retreat.
Climate Change is Real: Should We Adapt Or Work To Reverse the Change?
Homo sapiens has proven himself to be clever when he wants to be, and downright ingenious when he has to be. For example, the thinning of the ozone layer has been reversed. But given the political realities, climate change is here to stay. The world of tomorrow may be an enjoyable place to live. But it will undoubtedly be a different place — most conspicuously weather-wise.