Global Warming: Myth and Reality, Part II
In Part I of this article, we busted three common myths about global warming. Here's the truth about three more.
It can be hard to separate myth from reality on the global warming front, because the issue is so politically charged. Why? Because it threatens economic interests and cherished sacred cows on both sides of the fence. Meanwhile, most people are unaware that the issue has been all but settled in the eyes of the scientists who study climate and the Earth's history.
The fact is, the best evidence reveals that climate change is real, and it's ongoing. In this half of the article, we'll shed light on some of the causes and consequences.
Myth 4: The Sun causes global warming.
This is a valid argument, since it's generally accepted that the sun has gotten hotter over the past billion years. But is that increase enough, over the geological short-term, to cause the global warming we've experienced in the last 40 years? Apparently not.
Scientists have been collecting data on changes in solar output for more than a century now, and while the steady 11-year up-and-down sunspot cycle is evident in these records, there's been no upward trend in the sun's output. Nor has there been a noticeable rise in cosmic radiation, as some have suggested.
One thing that has changed noticeably is the amount of carbon dioxide (CO2) in the atmosphere. CO2 is a major contributor to global warming. While some natural processes can cause a spike in atmospheric CO2, humans are demonstrably the greatest contributor in the past few centuries.
Myth 5: So it'll be a few degrees hotter. Big deal.
This may be most insidious climate change myth. While it's true that local temperatures change more than a few degrees every day, what we're talking about here is the average global temperature. Consider the following scenario, which illustrates just one consequence of higher average temperatures.
Let's say global warming causes an average temperature rise of two degrees Fahrenheit. That's enough to cause more ice to melt at the poles (because there will be more days when the temperature's above freezing). More meltwater means more water in the oceans, which means widespread flooding of low-lying coastal areas. Most of those areas have cities on them. Get the picture?
Myth 3: We can't do anything about climate change.
Is it too late to halt climate change? Indubitably. But that doesn't mean we can't slow it down before we hit the point of no return.
Entire nations are already working on cutting back on their CO2 emissions. The Kyoto Protocol (which the U.S. has so far failed to sign onto) is an important first step, but much more draconian methods are necessary if we're to get a handle on global warming.
It may be necessary for something like the scenario discussed in the previous section to occur before humanity gets serious about climate change. But if we can stabilize or cut atmospheric greenhouse gas concentrations, that will give us an opportunity to adjust to the changes and look for more effective solutions.
So there's hope. And even more importantly, there's no telling what the future will bring. Given the accelerating pace of our technology, it's possible that a practical method for stopping and even reversing global warning lies somewhere around the corner.
