Weekly Wellness News

March 26, 2007

Feature: Can We Reverse Global Warming?

Let's say for the sake of argument that global warming is caused only by carbon dioxide emissions (it's more complicated than that, but I want to keep the focus straightforward here). Let's also say that the US and a very small hand-full of other countries are responsible for the vast majority of CO2 emissions (again, not quite true, but close enough for argument's sake in this case). If we start with these two assumptions, can we, the Western world, actually stop global warming?

That's not an easy question to answer. There are several components to the answer, and I'd like to address the primary ones this week.

What would it take to drastically reduce CO2 emissions in the US? Well, that's asking a lot. For one thing, the two primary contributions to these emissions are power generation and automobile use. Are you willing to turn off your entertainment system, computers, lights, kitchen appliances, ...? As long as the demand exists for electricity, we'll have to continue producing it.

At this point, renewable energy is not abundant enough to supply even small cities, much less the country. There are many promising ideas, but few are practical yet. Nuclear power, though quite safe, has a bad reputation because of accidents early in its history and other countrys' use of poorly designed/unsafe reactors (Chernobyl, for one). There just isn't enough power to keep our country running without burning coal and other fossil fuels. Period. Without a significant change in our daily habits, pollution with continue to be heavy.

How about driving? How many of you are willing to give up your car? Take a look at any highway during rush-hour, and count how many cars are empty except for the driver. Public transportation isn't practical for many people, and relatively few are willing to carpool to work. Again, we need significant change in our daily habits to effect change.

Powering cars through alternate means, just like alternate power sources, isn't significantly advanced yet. There's a lot of fuss over hybrids, but they only make a 20-30% difference over comparable standard cars. Choosing a fuel-efficient car over a large, heavy one will have an impact, but again, not significant overall. As for hydrogen and electric cars, there's a different problem: while the car burns clean, it takes a LOT of electricity to refuel them. Where does that come from? Coal-burning power plants.

So unless we, as a country and as a world, can make some tough choices and give up some of the extravagance and excesses we're used to, CO2 emissions will continue to be high. These changes are possible, but they won't come easy. We have to decide it's worth it to make the change. Some of us have, but many have not. We've got a lot of evangelizing to do.

The next big question is whether we'll even see a reversal of the current effects, or even just a stop to the trend. While we don't have definite answers, we do know that the changes won't be evident in the short term. To understand why takes familiarity with time-lag effects. To understand what those are, let's think about the seasons of the year.

Summer is hot. We all know this. But the hottest part of the summer is not on or near the longest day, nor is it when the sun is most directly overhead. Ditto with winter and the coldest part of the year. Why is this?

Quite simply, it's because even though the sun isn't quite as high in the sky, it's still high enough to be warming the air noticeably. From the spring to the fall equinoxes, the sun is relatively high and is above the horizon for more than half of every 24 hour period. And the hottest time of year is closer to the fall equinox than to the summer solstice because of this continued heating after the longest day. Sure, it starts to cool a lot at night after late August, but the days are still very warm well into September in most places. The time of year that daily temperatures are most rapidly increasing is around mid-June, at the solstice, but daily temperatures are still going up past that. Only when the days start getting significantly shorter and the sun is much lower on the horizon do temperatures start to come down. Makes sense, right?

Well, the same exact effect is going on with global world temperatures. Even if we completely stop the release of CO2 emissions into the atmosphere, what's currently there will continue to have an effect for some time. Even if all emissions were stopped today, global temperatures would probably continue to rise for several years. Then, after the existing pollution finally starts to decompose, temperatures will likely stabilize, and then, after several more years (or decades? We don't know how long...) we'll finally see a return towards the more historical equilibrium.

But that's if we completely cut all emissions overnight. That's not going to happen. So what's more likely? We should probably expect that the current warming trend will continue for decades, and that a full reversal will probably not happen in the lifetime of even our great-grandkids.

We've got to make changes. But we've also got to prepare ourselves for the reality that we won't see the results of those changes anytime soon. It's still the right thing to do.

Can we stop global warming? If humans are truly the cause (or a significant contributing factor), then I think it's possible. I won't live long enough to know for sure, but I believe we can. The sooner we start, the easier it will be.

Other news

• Personally, I like a packed, humid, musty gym with no free equipment: Older adults prefer exercising sans the young [www.msnbc.msn.com]
• You can overdo it: Fortified foods: Too much of a good thing? [www.msnbc.msn.com]
• It never would have occurred to me: Experts: Don't take aspirin to curb colon cancer [www.msnbc.msn.com]

From the editor

You may have noticed that there are no references for the main story this week. That's because this week is more opinion and general science than my traditional reporting on current studies.

If you like this departure from the norm, let me know. And if you don't, well, let me know! I'm always open to any feedback from all of you. Feel free to tell me what you think of my material, my style, my ideas, or anything else. It's just a click away, see the link below.

Next week I'll talk about alternative and sustainable energies and shed some light on why we don't currently have more non-fossil options for power and car fuel. Why aren't there more electric and hydrogen cars yet? What's wrong with hybrids? Stay tuned...

Healthy thoughts,
Jeff

Your feedback is always welcome!

Not yet a subscriber? Click here to subscribe.

Copyright 2007, Jeffrey Eliasen.
Do not reprint without express permission from the author.
Forwarding is permitted if (and only if) the newsletter is
forwarded in its entirety (including this notice).