On Jan. 21, Brian J. Soden, professor of meteorology and physical oceanography at the University of Miami, comes to the library auditorium at Marian University for a presentation entitled "The Reality of Global Warming: Cold Facts on a Hot Topic" 7-9 p.m.
Soden is a Nobel laureate for his 2007 work as a lead author on the 4th assessment plan of the Intergovernmental Panel on Climate Change (IPCC), an award that Soden, the IPCC and Al Gore shared.
NUVO recently spoke to Dr. Soden about the issue of climate change.
NUVO: Talk about your background and what got you interested in the work you're currently doing?
Soden: My undergraduate degree was in marine science, and I went on to get a PHD in the area of geophysical sciences and then went on to do postgraduate work and was a research scientist at the Geophysical Fluid Dynamics Laboratory in Princeton, New Jersey where we focused on developing and testing climate models that are used to project changes in the climate.
NUVO: A recent Pew Research poll found that those who believe there is solid evidence of global warming declined from 71 to 57 percent, and those who feel that global warming is caused by humans decreased from 47 to 36 percent. What is your response to that kind of public sentiment?
Soden: A lot of that would be because the general perception goes by recent weather trends, so it's a very short time scale perspective that people tend to focus on. For example if last summer was unusually warm or cool that would tend to sway their opinion that global warming was real. Or if there are extreme events like Hurricane Katrina, even though there's no association between global warming and Hurricane Katrina per se, just a very dramatic high profile event like that influences peoples opinion. Global warming is more about the longer term trend in the changes of climate, which take place over hundreds of years. If tomorrow is really hot, that has no meaning on the validity of global warming.
NUVO: How much of what we see as climate change is caused by people, or can you even say?
Soden: Well it varies on what you are actually talking about. If you look at the increase in global mean temperature over the last fifty years, the vast majority of that is associated with human activity and the burning of fossil fuels. There are other changes which are much less sensitive. For example, variability with hurricanes in the Atlantic is associated with natural variability as opposed to human influence.
NUVO: What mechanisms have historically been responsible for a rise in global temperatures and why are these not the primary culprits now?
Soden: There are things like changes in the amount of energy from the sun that can affect climate, and other processes like volcanic eruptions can affect climate. But we know that changes in the amount of energy from the sun haven't caused recent warming because over the last fifty years there hasn't been any increase in the amount of energy coming from the sun. Solar activity, volcanic activity, and internal mechanisms can cause changes in climate, but none of these changes can reproduce the warming that we've seen. So the only explanation we have, the only physical process we have that can explain the warming over the past fifty years is human activity, the burning of fossil fuels. There's no other mechanism out there that can do that. So despite skeptics' arguments that there is some other process responsible, there is no hypothesis and there is no testable theory that can explain these events.
NUVO: How much confidence should we have in theoretical models of climate change?
Soden: There are some models that we have very low confidence in, things like changes in the frequency of El Nino events. One thing we have confidence in is the ability of models to re-produce observed changes in temperature. We can test the changes in climate that we've seen over the 20th century, or changes in the climate that we observe on shorter time scales, changes in precipitation, moisture and wind patterns that we see during an El Nino event, models can reproduce many of these things. There are a number of different ways that we test models, and that is what a lot of my research is based on, trying to test the veracity of these models.
NUVO: Do you think that current IPCC models are too conservative in areas, are they too far fetched in other areas?
Soden: Like they say, all models are wrong, but some models are useful. There is no perfect model, all models are going to err. They may overestimate some changes, but they may also underestimate some changes. And we've started to see the evidence of certain changes in climate that are occurring much, much faster than we ever expected. Things like the loss of sea ice in the Arctic Ocean, dramatically faster than anyone projected. Also, sea level rise is occurring faster than we expected. The increase in melt and runoff from Greenland is occurring faster than we expected. For someone living in a low lying area like Miami, these are very alarming.
NUVO: Can you talk about some of the other effects of global warming?
Soden: Traditionally when we talk about global warming we mean an increase in global mean temperature. But the way it affects society are through changes in extreme weather events. Now there can be both good and bad in that. We've gone through a record breaking cold spell here in south Florida. Extreme cold events should become less common, so this is truly anomalous what we're experiencing right now. The likelihood of something like this happening in 50 or 60 years is going to be much more rare. Almost all the other events don't work in our favor, heat waves will become more frequent and more severe. Extended periods of well above average temperatures may occur. Heavy rainfall events are going to become more common, making places susceptible to flooding even more vulnerable. Droughts are going to become more common and more severe, simply because there is more back-radiation from the enhanced greenhouse effect that is going to dry out soils in between the rain events. When we get rain it's going to be more intense but those periods are going to be spaced further and further apart. It's not an issue of a global mean temperature increase that people are really going to notice, it's in terms of these extreme events.
NUVO: Are heat waves, floods and droughts the most imminent, and the most threatening?
Soden: That's an interesting question in terms of imminence and threat, that would depend on where you live. In South Florida I'm not too concerned about droughts, but sea level rise would have me more concerned. It's going to be very local, you have people living in sub-Saharan Africa, an increase in frequency in droughts and they're much more vulnerable. A change in climate isn't an inconvenience to them, it translates into death and mortality. So it's a different perspective there. And that is sort of a general truth in all this, that the lesser developed countries are much more vulnerable to changes in climate than the United States. We're the richest most powerful country in the world, we can pretty much adapt to whatever is thrown at us from global warming.
NUVO: What kind of changes can we see in the Midwest, I don't know if you can be specific enough to say Indiana, but-
Soden: (laughs) No I can't. In general, the truths are that you have droughts floods and heat waves, I know I grew up in the Midwest, in Indiana you get ALL of those things, but the frequency of those things will become more common. So I think that's the most pronounced way that these manifestations of global warming will present themselves. They will have an impact financially and an affect on infrastructure and that's where people will notice it. You may get longer growing seasons, and you'll start to see spring come sooner and sooner and winter ending earlier, starting later, but it's really in terms of the extreme events. And on the good side you'll have less extreme cold events.
NUVO: What could we do to mitigate climate change?
Soden: There are all sorts of ways to mitigate. Burn less fossil fuel in any way you can, through conserving energy, becoming more energy efficient, finding an alternative energy source, all those things address that. And there's carbon sequestration, where you take the carbon and pump it underground, any way to pull anthropogenic greenhouse gasses out of the air or just prevent it in the first place.
NUVO: What has been the focus of your most recent work?
Soden: A lot of my work is in two areas: one, testing climate models to see how much we trust them, what aspects are they good at, what aspects are they not good at. And the other is focusing on changes in extreme weather events: heavy rainfall events, hurricanes, how much hurricanes are affected by global warming, extreme windstorm events. We're doing research on hurricane tracks, one area I have a student working with me is on how global warming may affect the tracks that hurricanes take. Will they be more likely to head straight for the east coast or will they be more likely to curve out into the open
NUVO: What are you going to be focusing on at Marian?
Soden: I'm not going to try to tell people what to do, that's not my job. I'm not an advocate coming to tell people to buy hybrid cars or anything like that. My role is just to inform them of the scientific assessment of global warming. I'll try to give them as much information as possible so that they can make an informed judgment for themselves about what should be done.