 My name is Lonnie Fister. I work for NASA Ames Research Center. I'm interested in water vapor and dynamics in the lower part of the ozone layer, the stratosphere. I have a meteorological background. I analyze aircraft data and the main motivation is looking at water vapor in the upper part of the weather layer or the upper troposphere as it enters the stratosphere or what is better known as the ozone layer. The significance of that is that although we have a pretty decent understanding of how water vapor varies as the climate changes in the troposphere, our understanding in the stratosphere is not as good and it does have an impact. There have been some studies that suggest that maybe 10-20% of global radiative forcing is related to water vapor changes in the stratosphere. Basically, radiative forcing is a way that scientists describe how greenhouse gases and other things like aerosols, volcanic aerosols, affect the climate in a basic way. For example, we know that carbon dioxide changes the radiative balance of the surface by effectively putting a blanket. That has a certain quantitative radiative forcing on the whole earth atmosphere system. Then there are a whole bunch of other things like aerosols. When I say water vapor in the stratosphere has a radiative forcing impact, the order of 10 or 20% based on some recent radiative studies, I'm comparing it to the whole gamut of effects, aerosols, greenhouse gases that are sort of driving this climate change that we're seeing. Meteorological measurements have been fundamental for... I can't know when they started making balloon sonnings, but probably on the order of 100 years ago. What we now have is the ability to forecast weather and also to compare current weather to what we had before. We have a long history of a variety of measurements. The most fundamental of those are probably the surface stations that are all over the globe where we can actually derive a measurement of surface temperature over the past 100 years. We've done this before with other things, tree rings, glacial cores, and things like that. I'm going to start with the man-made meteorological network. Then there's a network of radiosons throughout the globe, mostly on land. Some places are more reliable than others. In the United States, you've got stations every 300 kilometers that make measurements twice per day. Over the Pacific, you've got almost nothing. China and Russia and Europe are in good shape. The tropics are not in good shape. That's another thing. These balloon sonnings, they go up to 20 or 30 kilometers. They cover the relevant parts of the atmosphere to the problems that I'm talking about, the stratosphere and the troposphere. Then there's the satellites, which is the great thing that's happened now where we can get global coverage of temperature and water vapor. Those are the fundamental things that drive the weather and drive the climate. We don't actually have reliable global measurements of carbon dioxide, a major greenhouse gas. We're starting to get that now with the OCO-2 satellite, which was launched about six months ago. There's also a Japanese satellite that was launched earlier that is giving us those kinds of measurements. That's a basic round of the meteorological measurements that we have. You can look at and think about it this way. If you want to get good horizontal resolution, you have to look down. That's called nadir-sounding. What you see there is radiation coming up at you at a variety of wavelengths. Depending on the wavelength you look at, you're looking at a different region of the atmosphere. This gets into spectroscopy and edges of spectral lines, mostly from carbon dioxide, which is the most radiatively active gas in significant quantities. The bottom line is if you look down, your vertical resolution is very limited, even using these sophisticated spectroscopic techniques. It's maybe about three or four or five kilometers even. Of course, there's a lot of much finer resolution structures in the vertical, in the temperature structure that you need to resolve. That's the limitation of satellite data that way. One of the things that we've been able to do in terms of improving forecast models is instead of trying to derive the temperature profile and sticking that into the model to integrate and get a forecast, we actually just take the raw radiances and stick those into the model. There have been some improvements and techniques about dealing with just this problem that you mentioned. The other way of looking at that, you can look down and get good horizontal resolution but poor vertical resolution. You can look to the side, to the limb, to the edge of the atmosphere just kind of skimming down. Then you get good vertical resolution, but then your horizontal resolution is 300 kilometers because you're looking at some sort of integral along the edge. So there are these compromises that you have to make. We have focused mostly on, in my specific research, mostly on the tropics. I think a lot of the activity in the lowest part of the stratosphere, which we're observing by aircraft and temperature changes, are probably related to changes in convection rather than the radiative driving, which is going to be more of a factor, say, at higher latitudes. But yeah, that is a prediction and I believe it has been, to some extent, borne out by some of the data. One of the things to keep in mind is that you don't necessarily want to wait until these things become terribly obvious, certainly because of the length of time that CO2 stays in the atmosphere. By that time, it's arguably getting a little bit late because you could stop producing CO2 and you still have to wait many, many, many decades for that stuff to come down. I think that the way I would respond is point to the things that are already happening. Especially in the Arctic where models predict and where we know that the warming and the changes are happening more rapidly. We see, some see level rise. We see the consistency between the basic evolution of the globally averaged temperature and what the models have predicted, including some of the past history, like some of the leveling off that we saw with the increase in the aerosols as coal production was increasing in the mid part of the 20th century. Look and see what's happened, how the models have done, and look and see what's happening now. To my mind, you're never going to convince everybody. To my mind, I think when you look at poles, I think most people are now convinced that climate change is real. I would argue that we know the earth is warming. We know we're causing it. What I would say is perhaps the major impact that people need to worry about is sea level rise. That's going to have an immediate effect because so many people live near the coast. We already know that the West Antarctic ice sheet or a good chunk of it is irreversibly melting. It's going to take a while. This is not going to flood your house tomorrow or even flood your children's or grandchildren's house, but it's happening. That I think is what I would point to, where I think we really know that this is the case. There have been issues of, well, we'll have more hurricanes. Well, that's not proven. There are a lot of unsolved details that are important details. People have argued that there's going to be more severe weather. I think that is certainly still a subject of scientific dispute. I think what is probably not in dispute is the rising sea level, and also we'll probably get more incidences of severe rainfall. That is fairly well established at this stage. But I think that we will probably be, as we pursue this research on weather impacts, I think we will be able to find that the likelihood of severe weather will increase in this warming climate. We've got all this moisture in the atmosphere. Moisture represents a source of energy. I would think that things will get more energetic, but there's details that have yet to be worked out. Heat waves are going to go up, if nothing else, because we're increasing the average temperature, and there is clear evidence that we're actually increasing what I would say is the variance. That is the deviation from that average temperature in both directions. I started out being interested in science. I was going to study planets, and then I got interested in a meteorology course in my senior year in college. One of the great synoptic meteorologists of the day was teaching that course, and he was very encouraging. I enjoy the class and got involved in atmospheric science. It's probably worth pointing out that my father was a scientist, too. He studied the ionosphere. I've come down in the world, so to speak, at lower levels. When I got to NASA, they were doing work with aircraft data. I started analyzing aircraft data, and I combined that with what I knew about the stratosphere and my training in graduate school. That's pretty much where I am now. At NASA, we pursue research that NASA is interested in. It's a little different than some of the other agencies where it's all investigator-initiated. To some extent, you're a little bit guided by your management, which is okay. There's a place for that in science, and there was a lot of interest in this subject. So I pursued it. I think it's the most important planet, because it's the one we live on. I think we should try to get to others, but that's a much longer term. We better watch our own climate, because I think that if we don't watch it, it'll change faster than we can possibly move to another planet.