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Planet Earth: Our Loving Home
Understanding Planetary Climate Systems: An Interview with Atmospheric Scientist Dr. Donald J. Wuebbles

Astute viewers, welcome to Planet Earth: Our Loving Home on Supreme Master Television. This week we’ll find out about the hugely damaging environmental impact of climate change with Dr. Donald J. Wuebbles, Harry E. Preble Endowed Professor in the Departments of Atmospheric Sciences and Electrical and Computer Engineering at the University of Illinois at Urbana-Champaign, USA.

Dr. Wuebbles has a PhD in Atmospheric Sciences from the University of California – Davis, USA and has authored over 400 scientific articles, most of which concern our planet’s atmospheric composition and its effects on the global climate system. He is noted as the first scientist to statistically prove that stratospheric ozone was depleting in the early 1980’s and was honored by the United States Environmental Protection Agency in 2005 with the Stratospheric Ozone Protection Award for his overall work in this area.

Dr. Wuebbles was a lead author on the first and second assessment reports by the United Nations Intergovernmental Panel on Climate Change (IPCC) and shares in the 2007 Nobel Prize for his work with the Panel.

We know that the climate is changing, that it’s not just the Earth is warming; it’s many other aspects that are going on; precipitation patterns are changing and other aspects and we have clear evidence that the basis for those changes is because of human activities and particularly the emissions of carbon dioxide and some other gases and particles that are in the atmosphere that are causing a forcing on the climate system that is driving that change.

One serious outcome of rising global temperatures is an increase in the frequency and strength of extreme weather events such as hurricanes, floods and droughts.

Well, this year (2011), actually, was the worst year on record for natural disasters in the U.S. – over US$35-billion of damages. Some of that was due to hurricanes and earthquakes and things like that. But a good part of it was because of major storms that occurred, causing flooding; for example, the Midwest and the South, near the Mississippi and other, associated rivers, wildfires occurring in the Southwest related to large temperatures that were occurring and a number of other such things.

What we’re thinking is, unfortunately, that kind of uncommon event is likely to become more common in the future as we look at the changing climate. We really expect increases in the severe weather as a result of climate change and that’s what we’re seeing. Every part of the US has seen an increase over the last 50 years. In the Midwest, that’s been over a 30% increase in the top 1% of storms, so more precipitation is coming.

Well, that means more flooding; in particular, it’s tending to come that way in the winter and spring, so more flooding. And what we’re seeing also in areas that aren’t getting those increases overall in precipitation like we’re seeing in the Midwest, if we go to the Southwest, for example, when they do get rain, it still tends to come as larger events than it used to, but they’re not getting as much rain as they were before. And so that’s why in Texas (USA) this year we had a really major problem with a really major drought.

The public typically associates climate change with unnaturally hot weather, but it can also lead to very harsh, abnormally cold weather in certain regions as well. The substantial warming occurring in the Arctic is materially changing the weather patterns in other parts of the world.

So we expect more warming in higher latitudes because of several important feedback processes that occur in the climate system. One is called the Ice-Albedo Feedback. What that means is as the ice in the Arctic melts you have less ice on land or less ice in the ocean. The background, what was covered with ice has less reflectivity. And that causes more absorption of sunlight and you get warmer temperatures. So what does that do?

Because the temperature gradient between the Arctic and mid-latitudes is decreasing, the jet stream becomes weaker. And the net result is that large what we call “extra-tropical storms” are moving further northward. And that’s tending to leave places like Texas (USA) and the Southwest and Southeast drier and so more likely to have a drought than before. But it’s also part of the reason why we’re seeing this increased precipitation in our area (the Midwest).

At the same time, the other key factor there is that you can get more Arctic air coming down to mid-latitudes. And so in the winter, you can actually end up with colder temperatures for short periods compared to what you would have had previously. So you can end up with a large snowstorm that can drop 36 inches of snow in Washington DC (USA) and actually have that relate very strongly to our changing climate.

Shifts away from normal weather patterns also have detrimental effects on human and animal health; one reason for this is that certain diseases that rely on vectors or hosts spread as suitable environments for the hosts enlarge.

For example, malaria, which is transmitted by the Anopheles mosquito, is mainly confined to tropical areas, but as the world warms, more regions will provide suitable conditions for the mosquito to thrive, thus causing marked increases in malarial infections. The Wildlife Conservation Society has identified 12 diseases that are likely to spread to other areas due to climate change, including bird flu, cholera, plague, Ebola, tuberculosis, Lyme disease and babesiosis.

However, increased incidence of disease is not the only climate-change-induced factor that will significantly affect human health. Water and food shortages and more dust storms will also have a tremendously negative impact on our longevity and quality of life.

One of the things that I have a particular concern about is pollens. I have allergies; many, many Americans have allergies to pollen. And as the climate is warming, as the weather patterns are changing, we’re tending to get more weeds. More weeds means more pollen, and so more concerns about those kinds of allergies than we had before.

In addition, as the climate changes, we expect more issues with air quality. The same amount of emissions that lead to concerns about ozone are actually exacerbated or made worse by warmer temperatures.

We expect that as the temperature’s warming, we’re more likely to have pathogens and insects and things that can cause major, major health problems all come into a region that maybe you didn’t see before. So there’s a wide range of possible impacts on human health as a result of the change in climate.

The economic cost of a hotter planet is also predicted to be extremely large; a 2005 study by Claudia Kemfert of the German Institute for Economic Research estimated that climate change will cost up to US$20 trillion by 2100. However, another figure calculated by British scientists for the European Commission's Directorate General for the Environment put the sum at US$73 trillion by 2200.

A report for the British Government by the World Bank’s former chief economist and past advisor to the UK government Lord Nicholas Stern states that inaction on climate change will substantially reduce the world’s economic output by the end of the current century.

There have been a number of statements put out that the cost of inaction is far greater than the cost of action. And it is much better to do something now than wait because of the extreme expense.

One analysis by a number of top economists was led by Lord Stern from the UK. And in that analysis, they said that we may have as much as a 20% decrease in the gross domestic product worldwide by the end of the century if climate change continues to occur at the rate it is, if we don’t do anything about the burning of fossil fuels, etc. So that would be a dramatic impact on the economics, affecting everyone on Earth.

Another report by the Netherlands Environmental Assessment Agency, entitled “Climate Benefits of Changing Diet,” states that a planetary shift to a completely plant-based diet would result in an 80% reduction in the costs of mitigating global warming by 2050, because producing animal products is extremely intensive in terms of energy use and emits very harmful greenhouse-gases.

Many of these gases such as methane and nitrous oxide generated in the process of raising factory-farmed animals have global warming potentials far larger than that of carbon dioxide. For example, over a 20-year period, methane is 72-times more potent than carbon dioxide at warming the Earth and if aerosol interactions are considered, the gas is actually 100 times more potent; however it is shorter-lived compared to carbon dioxide.

Methane stores in the atmosphere for 10 years, which means that after you emit a certain amount of methane, 10 years later you can expect a little over 60% of that, maybe almost two-thirds of that gas has been removed from the atmosphere through reaction. And then the rest stays there for another 10-year period. And you reduce another 60-plus percent of that and then, nitrous oxide's even longer. It's like a hundred years. (CO2 has an initial lifetime of a hundred years.

But then after that, it depends on the rate of the CO2 being removed into the deep ocean. So the second lifetime, second e-folding rate, we call it, would be maybe more like a thousand years. So, CO2, once we emit it, stays around for a long, long time. No question about the importance of methane and nitrous oxide and some other gases in terms of their effects on climate and are very much a concern.

What do think about the government shifting subsidies away from livestock and toward organic vegan farming as an effective and even money-saving policy to help reduce global warming?

I think anything we can do towards promoting going vegetarian and vegan would be really good. As a scientist, I don’t tend to talk about policy and say well we should be doing specific things with policy. But certainly, I think the science tells us that we could help with these concerns about sustainability and climate concerns by reducing our use of meat and animal products, so we should be looking at ways we could do that effectively.

Thank you Dr. Donald J. Wuebbles for taking time from your busy schedule to talk about the effects of climate change on our world and for your important scientific work in this field over the years. May enjoy continued success in your future research endeavors.

For more information on Dr. Wuebbles, please visit www.Atmos.Illinois.edu/people/wuebbles.html

Conscientious viewers, thank you for watching this week’s episode of Planet Earth: Our Loving Home. May we always respect and protect our beautiful planetary abode.

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