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Edited recording of Dr. David Poister's call: click here. https://soundcloud.com/charterforcompassion/science-of-climate-change
Power Point presentation used during the call: click here. https://old.charterforcompassion.org/images/menus/Events/David_Poister.pdf
Agenda
Welcome and Introduction (Reed Price)
Discussion and Slideshow (David Poister)
Questions (Facilitated by Reed)
Conclusion
About the Speaker
This information, as well as information about the other speakers during the Earth Week Speaker Series, is provided in the announcement on the Charter for Compassion International website: http://www.charterforcompassion.org/index.php/environment-reports-and-documents/earth-day-speaker-series-and-presentations-2016
David Poister, david.poister@snc.edu, is a Professor of Chemistry and Environmental Science at St. Norbert College in Green Bay, Wisconsin where he has taught since 1995. He received his B.S. in Chemistry from St. Francis College in Loretto, Pennsylvania and his M.S. and Ph.D. in Water Chemistry from the University of Wisconsin - Madison. An environmental chemist with research interests in biogeochemistry and the chemical ecology of aquatic systems, his current research focuses on chemical interactions between algae growing in Wisconsin’s Fox River. In addition to his scientific work, David is interested in exploring how the dialogue between science and religion can be used to understand and advance the human condition. David and his wife Sara have four children and live in De Pere, Wisconsin.
Summary of the Call
Although the techniques used by scientists to measure and predict the effects of climate change are complex, the fundamental physical and chemical processes that cause these changes are quite understandable. This presentation will explain these processes to give participants without a scientific background a basic understanding of climate change science.
Introduction
Reed: Good morning, this is Reed Price from the Charter for Compassion International. I’m very happy to welcome you to the presentation today. Dr. David Poister will be presenting to us. It is the continuing Earth Day Speaker Series that we’re involved in, and today we’re talking about the science of climate change. We’re very happy to have Dr. Poister with us.
He is a Professor of Chemistry and Environmental Science at St. Norbert College in Green Bay, Wisconsin where he has taught since 1995. He received his B.S. in Chemistry from St. Francis College in Loretto, Pennsylvania and his M.S. and Ph.D. in Water Chemistry from the University of Wisconsin - Madison. An environmental chemist with research interests in biogeochemistry and the chemical ecology of aquatic systems, his current research focuses on chemical interactions between algae growing in Wisconsin’s Fox River. In addition to his scientific work, David is interested in exploring how the dialogue between science and religion can be used to understand and advance the human condition. David and his wife Sara have four children and live in De Pere, Wisconsin.
If you have any questions during this conversation, please press one on the phone keypad of the phone you used to dial in. That will show a little hand on the interface here, so that I can recognize you and virtually hand you the microphone. If you have a problem, please press 5 and someone will try to take you aside and help you out.
Good day, Dr. Poister. We’re very happy to have you here.
Discussion and Slideshow
David: Thank you Reed, and thank you for your help in setting this up. I’d also like to thank Barbara Kaufmann here in Wisconsin who invited me to share this information with you, and I’m happy to do so. As Reed said, I’m a professor of chemistry and environmental science at St. Norbert College and that’s really been the source of my recent interest in this topic. St. Norbert is a Catholic College and a little over one year ago, Pope Francis published an encyclical on the environment and since then, the college and groups related to the college have been interested in learning about how humans have impacted the earth. The image that you’ll see on your screen shortly illustrates that. This image is created by combining some space based photographs of the earth at night. You can see that humans have generated enough visible light that you can actually see that from outer space. That scale of human activity is what we’re talking about today.
There’s a lot to talk about in terms of climate change, so I’ve divided the talk into two parts. The first part will be just the science, and the second part of the talk will be our response to that. I don’t want to work on developing the response, but to give you information that you might find useful in responding to climate change.
So to start with the science part, I want to come at explaining this by thinking about the earth’s energy budget. You can think of the earth’s energy budget as being like a monetary or financial budget. You have a bank account, just like the earth has a certain amount of energy associated with it. Money flows into and out of that bank account, just like energy flows in and out of the earth. The key to understanding the energy budget of the earth is to understand that there are different forms of currencies that the money goes in and out of the account. Thos currencies for the energy budget are the different forms of electromagnetic radiation, which is nothing more than different wavelengths. We’re all familiar with visible light (VIS): these are the wavelengths that we can detect with our eyes. We could describe those as having a medium wave length or energy. Shorter waves with higher energy are called ultraviolet light (UV) and longer wavelengths have lower energy and they’re called infrared (IR). Those are the three forms of currency for the budget that we need to remember. Wavelength is inversely proportionate to the energy.
Now, let’s look at the cash flow in and out of the earth’s energy account. Most of the energy associated with the earth at its surface is generated at the sun. If you look at what hits the earth’s outer atmosphere, it is a combination of mostly UV and visible light. But that is not what makes it to the surface of the earth, and this is our first interaction between the currency (the electromagnetic radiation) and the atmosphere that we’re going to see. Because as this light travels through the atmosphere, most of the ultraviolet light actually gets absorbed by the atmosphere. Gases such as ozone and oxygen in the atmosphere remove most of the ultraviolet light so that what hits the earth‘s surface is mostly visible light with a little bit of UV light on it. Once it gets here, most of it just gets bounced right back out into space. 60% of light that hits the earth’s surface gets sent back into space, in the same wavelength, the same form, the same currency. So it came in as visible and ultraviolet, and it leaves (when it gets reflected) as visible and ultraviolet. You of course know this is true, that reflected light doesn’t change its wavelength by the fact that if you look in the mirror your clothes are the same color as they are if you look right at them. The reason for that is that different colored lights have different wavelengths and the wavelength that is reflected directly off your shirt is the same as that coming off the mirror. So that reflected light gets shot right back out into space.
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The stuff that doesn’t get reflected, that 40%, gets absorbed by the earth’s surface. That is what is responsible for increasing or warming the earth’s temperature. It also is absorbed by plants and supports photosynthesis (which of course is the basis for most of the food chain on the earth)
So now we have the inflow, our income if you will. Now let’s think about what happens inside the bank account. If all you did was deposit and not spend, you’d have a big bank account. In terms of the earth energy, that would be bad because the earth would burst into flames. So obviously we spend too, the earth also loses energy. The key to understanding global warming as part of climate change is to realize that when the earth loses the energy, it is in a different form of currency. The earth emits energy not as visible or UV light, but as infrared light (the longer wavelength). The reason why this is important is because this outgoing infrared radiation interacts with the atmosphere in a very different way. It is absorbed in the atmosphere by green house gases like carbon dioxide. Once the gases absorb this infrared light, they move into a higher energy configuration. The atoms in the molecules move in a different way relative to one another. The energy gets transferred to these molecules, and they kind of get juiced up in regards to their energy.
These molecules can’t maintain that energy state, so they eventually release their energy as infrared radiation. But this radiation gets emitted in a random direction. So while infrared is emitted from earth out into to space, it gets absorbed and then redirected by the gases in the atmosphere, and a bit of infrared will actually go through many absorptions and re-emissions before it ultimately either makes it out into space or it gets back send to earth. The stuff that comes back to earth increases the earth’s temperature. We call this the greenhouse effect.
I think a more apt analogy would be a blanket. A blanket keeps you warm not by generating heat, but by retaining heat that you yourself are generating. That’s what the greenhouse effect does. The greenhouse effect is a naturally occurring part of the earth’s atmosphere. You could even say its an essential part of the earth’s atmosphere because without the greenhouse effect, the average temperature on the earth would be about 5 ºF. However, the average earth surface temperature is 59 ºF which makes it habitable.
You actually have some experience with the greenhouse effect because you know that the coldest nights happen when the air is dry. This is especially obvious in desert climates. During the day it’s very warm, but once you turn off the source of energy it gets very cold because water vapor is a gas that does what carbon dioxide does; it’s a green house gas. Carbon dioxide is the main human-made cause of or enhancement of the greenhouse effect, but there are others as well: methane, chlorofluorocarbons, ozone, tropospheric, and nitrous oxide. But most of the warming that we see due to the greenhouse effect is coming from carbon dioxide. So if this is true, if this has been happening since the earth was formed, one would expect that if the thickness of the blanket has increased, we would see a corresponding change in the earth’s temperature. And we have seen that, and I want to talk about how scientists have observed this relationship.
This is a figure from the coring site in the Antarctic ice sheet. Scientists have taken a plug of ice that is over 3.5 kilometers long and they have removed that from this large ice sheet and they take this plug of ice and what they have is a chronology of ice formed over the last 420,000 years. The important part of this is that when that ice at the bottom of the core was formed, it trapped bubbles of gas inside the ice. That gas is the earth’s atmosphere at the time. So these ice cores have preserved samples of the earth’s atmosphere from hundreds of thousands of years ago. Scientists then take these cores up and melt the ice to analyze the gases that come out of them. And when they do that, they’re analyzing the earth’s atmosphere for composition from 420,000 years ago.
This is a graph of the earth’s temperature (in blue) and then the carbon dioxide in the trapped gas (in red). When carbon dioxide goes up, temperatures go up. If you go all the way to the right end of the graph, you’ll see that we are currently in a period of increasing carbon dioxide and increasing temperature. What we talk about with regard to the enhanced greenhouse effect, you can’t even detect it on that because it’s so recent. That recent increase in temperature is us coming out of the most recent ice age.
So far, everything is well and good. Carbon dioxide naturally varies over time, as does temperature. But In the middle of the 20th century, scientists started to think that perhaps some human activity might be enhancing the greenhouse effect. What you’re looking at now is the Mauna Loa Observatory in Hawaii. The reason why it’s such an important site is because people (beginning in the middle of the 20th century) have been measuring the composition of the earth’s atmosphere. They do this by taking direct measurements of how much carbon dioxide and other gases are in the air in (in this case) the northern hemisphere, which is where Hawaii is.
This saw-tooth graph shows what they’ve found – the increase in carbon dioxide in the earth’s atmosphere since the mid 1950s when measurements started. You can see there’s been a gradual and continual increase in Earth’s carbon dioxide concentration. We have seen a thickening of the blanket, what is called the enhanced green house effect or global warming.
Now, I think there’s a lot of confusion regarding the last two graphs that I showed you. I showed you a graph that showed this happening over the last several hundreds of thousands of years. That’s natural - that can’t be due to human activity because humans have only been present for the last slice of the graph.
But that second graph, we have never before seen CD concentrations rise so rapidly. Our current (say the last century) carbon dioxide concentration is ten times more rapid than anything ever observed before in our geological record. This is unlikely a natural phenomenon.
Let’s talk about the effects. My main source of information is available to everyone. Some of the technical stuff might not be very accessible but it is publically available and out there. It is published by the intergovernmental panel on climate change. This group essentially takes stock roughly every five years of our current knowledge of climate change as far as causes, consequences, etc.
What I’m going to talk about next is the result of the enhanced greenhouse effect/global warming. Not surprisingly, we see an increase in temperatures. As the blanket gets thicker, the temperature goes up. We have seen that throughout the 20th century that temperatures have gone up and in the last few decades they have gone up at an increasing rate. We have an increased blanket thickness of carbon dioxide primarily.
The thickness of the blanket has been going up (we’ve already seen that), but this graph shows our annual emission rate of greenhouse gases. So, not only is the blanket getting thicker, but according to this, the emission that contributes to the blanket thickness is increasing. We have a faster rate increase of emission every year. This is unlikely to go away given our current human activity.
The other thing to point out about our temperature change is that it is not uniformly distributed over the earth. And this map shows that. The squares in white are areas where we don’t have data to make predictions for. Most of the earth has gotten warmer, but that warming has not been uniform. Some places have gotten hotter than others. One of the general trends is that northern mid to high latitudes is where we see the biggest increase in temperature, especially over land. So that’s where you’re seeing the purple (Russia, North America). What is driving this is something called the albedo effect. The albedo effect is just the effect of color or reflectivity on how much heat gets absorbed. This is why a black car gets hotter in the summer than a white car. If we take a dark surface on the right and a white surface on the left, and we shine electromagnetic radiation on it, more of the light gets reflected by the white surface than the dark surface, meaning that the dark surface absorbs more light and temperature goes up further. Because the northern hemisphere has a higher land mass than southern (with the exception of Antarctica); we see a bigger change of albedo in the northern hemisphere. That’s because ice has a very high albedo, and exposed land has a much lower albedo. In the northern hemisphere where we have a greater land mass, as that land mass experiences less ice cover, we see more and more heat absorption. This is kind of a classic feedback loop that is present in a lot of aspects of the earth’s climate. This is just a graph of the northern hemisphere spring snow cover. The graph on the right is the arctic summer sea ice extent. Ocean covered with ice reflects a lot more light than ocean not covered with ice
As we’ve lost snow cover, we’ve lost reflectivity and increased temperature. This image shows the shrinking of that polar ice cap. One of the smallest extents of summer (this would be September) Sea Ice was in 2007, and you can see that there are parts of Siberia that now have open access whereas before they never had access via ocean lanes to those areas; they were ice locked. We’ve seen a big loss of ice cover and that’s a contributor to temperature increase in northern high latitudes.
But of course there is ice in other places, ice cover loss is not limited to polar regions. We can find it throughout the earth in higher altitudes where we have ice as well. That is the phenomenon of glacial retreat. What you’re looking at right now is the same glacier, photograph taken from the same point, looking at the glacier in 1941 and then in 2004. You can see there’s just much less glacier in 2004 than there was in 1941. You can see what was once a very thick ice sheet flowing into the bay is now open water with just a remnant of the ice sheet. This is not unique to glaciers in Alaska. This graph shows for a select number of glaciers that have been monitored, that almost all have seen a decrease in thickness.
While we’re talking about ice, maybe we can also talk about another consequence of enhanced greenhouse effect, which is where the ice goes once it melts. It ultimately flows into the ocean. We aren’t looking forward making predictions but just looking at what we’ve seen so far. We’ve seen an increase in average sea level. About 27 meters since 1900 as indicated by the graph on the right. This is coming from two places. The first place is the melting of the land ice (glaciers). When sea ice melts, it doesn’t result in ocean level rises because that ice is already displaced. But ice that’s on the land obviously has not been previously displaced. But actually, that doesn’t account for all of the sea level change. Maybe a little under half of sea level change has come from thermal expansion of water. When you increase temperature of fluid, it expands. So half of that 20 cm. rise in sea level has come from more water in the ocean, the other half has come from the water that’s there already is expanding because of temperatures rising.
So what are some concerns regarding this increase in sea level? I put this map up there. It’s a map of New York City. It’s an elevation map. The green color is land that is anywhere from 1-2 meters above sea level. You can see big parts of Brooklyn, Jersey City, and areas that are near sea level. You will recall that several years ago there was an evacuation from Manhattan because of concerns about storm surges. I think this that’s something to keep in mind when we think about the potential threat of rising sea levels, this will happen rapidly in geological time, but fairly slowly in the terms of the time over which humans observe things. But what I think we are going to seeing as a result of these higher see levels, increased inundation associated with storms. I think that will be the most observable effect. That’s why I wanted to show you that picture of Manhattan.
There are actually other places that are even more vulnerable to rising sea level. The classic example is the Maldives islands in the Indian Ocean. The average elevation of the Maldives is one meter above sea level. So predictions are that a reasonable estimate of sea level rise will be another half meter in the next 100 years. So looking at a nation whose elevation is just barely above sea level – that is a huge change in what those countries will have to deal with. We’ll talk more about sea level at the end of the talk.
There is also an effect on oceans. To get into the nitty gritty of how the atmosphere responds to climate change, it’s necessary to talk about oceans and ocean circulation. Oceans act as a kind of a sponge. If you sum up all of the carbon dioxide that’s coming into the atmosphere, and look at how much is remaining there (by looking at the income and the size of the bank account), you can see that a good bit of it is being removed from the atmosphere. It’s being absorbed or sucked up by the oceans. The blue lines on the graph on the bottom show increase of carbon dioxide in oceans. A consequence is that oceans have become more acidic. That’s a chemical effect of this increased carbon dioxide concentration.
Another thing that we have absorbed as a result of the increased heat content of the earth’s surface is the effect on the hydrologic cycle. Rainfall is driven by atmospheric water which is driven by evaporation which is driven by the heat which causes evaporation to occur. We have seen an increase in precipitation in some areas over the last almost 60 years, and a decrease in other areas. We’ve seen an increase in much of North America, but decreases in southern Europe, parts of China, and sub-Saharan Africa. We’re seeing impacts of climate change that are very non uniform from region to region.
At this point I’d like to talk just a little bit about future predictions, and how the IPCC deals with these future predictions. They have different scenarios. Their scenarios are represented here by these different mathematical models. The model which goes up to the highest as you move to the right (RCP2.5), would be doing nothing to decrease greenhouse gases scenario. The other one (RCP2.6) would be taking steps that would freeze our greenhouse gas emissions at 2030 levels. So those are the two scenarios that we’re looking at. The orange line represents worst case and the blue line would be best case we could hope for at this point.
So I want to look into the future in regards to the hydrologic effects. These models predict (this is kind of worst case scenario), they exaggerate the more likely conditions that we’ll see but none the less point out what the changes will be. You can see in the top left figure that some areas decreased precipitation while other areas had increases in precipitation. Keep in mind that precipitation is only part of the cycle. The other side that drives precipitation is evaporation.
The top right figure shows increased evaporation as a result of increase in heat. The bottom left shows an increase in run-off. Almost all models predict an increase in rainfall intensity. Those places where we see an increase in precipitation, that’s coming from more intense events. These high intensity rainfall events where the water does not infiltrate into the ground result in significant flooding. The bottom right graph shows soil moisture. There are key parts and much of the earth is predicated to have a decrease in soil moisture. Why is this significant? Because that’s what we use to grow our food. That is an impact we’re likely to see in the future. We’re likely to see regional changes in the conditions that we need to generate food.
And on that rosy note! Let’s move in and talk a little bit about the “response” side of things. I think the place to start with this, is to look at where the gases are coming form that are driving the enhanced greenhouse effect and that are ultimately causing the hydrological changes.
We can encapsulate where we’re at with this E.O. Wilson quote, who is a well known evolutionary biologist : “A very Faustian choice is upon us: whether to accept our corrosive and risky behavior as the unavoidable price of population and economic growth, or to take stock of ourselves and search for a new environmental ethic.” And I think obviously those choices need to be grounded in the scientific evidence we have at our disposal.
The first thing I want to look at is where are these gases coming form in terms of region or country. This graph was put out by the EPA in I think 2009 illustrating that the US is a significant source of greenhouse gases. China is listed as the second biggest piece of the pie. I think everyone would agree that China’s piece is probably larger than indicated by those numbers. China has actually recently admitted that their emission rates are higher than they’ve reported in the past. One of the reasons why I present this is because the United States is a significant contributor to these greenhouse gases that are increasing in concentration in the atmosphere.
If you look at what we do that generates these greenhouse gases, this next figure breaks down the U.S. emissions by sector: electricity, transportation, industry, agriculture, commercial and residential. If we want to focus our efforts in areas geographically and by activity, this gives you some information about those areas.
So what specifically can you do? I think there are two things.
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Do what you can to reduce or minimize your carbon footprint. Energy consumption in terms of transportation and electricity use. That’s kind of a whole different set of presentations!
The other thing is that a problem of this scale is going to require institutional change and response. We have some issues in the U.S. regarding public opinion about climate change. Not everyone agrees that the changes we’ve observed and are likely to observe are due to human activity. So there’s a political piece to this. This graph shows public opinion about how climate change is being discussed in the media. It shows a couple of things – it shows a low point in the public’s understanding or acceptance of human caused global warming in about 2010, that is what I consider to be a political aspect of this. 2010 was the first midterm election after the Obama election, and also the rise of certain movements within the conservative movement. These groups co-opted climate change for what I think is political reasons. The story of Bob Inglis who was a congressman from South Carolina is a good example. I think by any measure before his primary election for the 2010 general election, anyone would have agreed that Bob was kind of a classical, southern conservative. However, he publicly stated that he had examined climate change evidence and it was overwhelming and caused by human activity and we needed to start taking reasonable steps to mitigate this. He lost his primary for reelection to U.S. congress in 2010 and he was not the only person who was primaried out of their seat using climate change as a wedge issue. The remnants of that we can still see today in this presidential election cycle. I do think there was a time when there was a growing bipartisan consensus in American and I think we need to do what we can to go back to that point.
Just to give you some perspective of where we’re at in this country, right now 54% of Americans believe that human activity is causing global warming. This compares to 78% of Germans, 80% French, and 90% Chinese, which seems high for China but when you think about it, Chinese people are probably acutely aware on a daily basis of the extent to which human activity influences atmospheric composition.
Another way to view this problem is that 77% of scientists say climate change is a serious problem but only 33% of the pubic say that it is. Public opinion needs to drive institutional change, though.
The last thing that I want to talk about specifically for this group that I think will be relevant is that the impacts of this have a regional difference. But that regional difference is part of why there is going to be a disproportionate impact on these changes on actually the people who are least able to deal with them. This is a quote directly from the IPCC report “developing countries, on the whole, are more vulnerable to climate change than developed countries.”
There’s two main reasons for this. First is: the location of developing countries (where they tend to be). But also, they do not have the infrastructure to deal with changes that are going to occur at the rate at which we think they will.
This is an example to illustrate that difference. This is an elevation map of the world where we can see the dark red areas are the areas almost always right along the coast that would be most susceptible to the effects of sea level rise. I think the most direct impact is we will see more severe storm and surge effects in these low lying areas because we’re starting at a higher sea level.
So let’s just take this one problem and compare two countries. The United States. There are definitely vulnerable parts. If we take a look at areas below one meter of sea level, that corresponds to about .4% of the total land area, which 1.2% of population. I’m not saying that’s the only zone that we need to be concerned about, but it gives you a basis of comparison. That’s 3.7 million people that are vulnerable. That’s a lot of people in the U.S. That’s an issue that we’ll have to deal with.
But now let’s look at a different country. Vietnam. Vietnam has two very large low lying river delta areas. 5% is less than one meter sea level. That’s 11% of population, and a big chunk of its agricultural area. In Vietnam, that’s 9.9 million people as opposed to 3.7 million people in the U.S.
For groups concerned with the human condition, these types of issue s will be more and more a part of the conversation about how we deal with environmental problems on the global scale. I chose these countries because I could get data for them. All you have to do is look at the map and you’ll see that a good chunk of Bangladesh would be considered vulnerable to inundation and sea level rise.
So, with that, I’d like to lead back to the picture we started with that shows the lights created by our activity as seen from outer space. And at this point, I’ll open it up to questions or comments from the participants.
Questions and Conversation
Reed: Thank you, Dr. Poister. If you want to comment, raise your hand by pressing one on your keypad and I’ll be happy to pass the microphone to you and recognize you if you have a comment or question.
One thing that occurs to me, Dr. Poister, is the question of population. Obviously the world’s population is growing. Do scientists think we have enough levers or ways that we can respond outside of population, or will that inevitably increase that upward tick of carbon and green house gas emissions?
David: One response to the threats posed by climate change is that a technological fix is likely on the horizon. I think that my response to that would be, we actually have technological fixes in place already (the availability of renewable energy sources, etc.) but we aren’t really taking advantage of those technological fixes now. I think that’s largely driven by a need to develop the common will to implement those changes which will have economic impacts and will be difficult for some people.
I think the human population does have a component here and I think there are lots of other reasons to look at population growth in addition to this as well. If you look at what people studying population demographics have told us, is that the things that we need to do moderate human population growth are the same things we need to do to ensure equal rights for people in the developing world. So I would say that population growth is part of this puzzle. I don’t think we need to develop new solutions. I think we already have an indication of what those solutions might be. It’s a matter of implementing them.
Reed: You make it clear that transportation and electricity are two major components. And those are things that we have the capacity to control!
David: They are, yes. And I should add, there are some places that are leading the way more so than the U.S. in making changes. Germany is a good example of a country that is simultaneously reducing its reliance on nuclear energy sources, and increasing its reliance on renewable energy sources.
Reed: Is nuclear energy a contributor to greenhouse gas?
David: Not a major contributor; the extent to which nuclear energy burns fossil fuels would be the only extent to which that occurs. But the generation of electricity from nuclear energy is not a significant source of greenhouse gases.
Reed: We heard yesterday from Marc Barasch who is trying to re-green the world and look at reforestation, is the advantage of looking at agriculture and forestry in a way that might be more supportive. I imagine that could play a role in mitigating the warming issue, the reflective issue that you were talking about.
David: Yes, definitely. If you look at the data for the overall global scale carbon cycle, the carbon that is contained in biomass and forests and trees would be part of that sector. The carbon contained in biomass is actually increased in much of the northern mid latitudes. We’ve actually seen, even in North America, an increase in total forest cover. Mostly what used to be pasture land goes back to forest land through succession. But that has been balanced by forest lost in tropical areas. The key difference there is that tropical forests cannot regenerate the same way that temperate forests in higher latitudes can because tropical forests have very nutrient poor soils, whereas in the colder climate of higher latitudes, if you just allow that vegetation to reestablish itself, it will. And it is, now going back to a forested region. But in tropical areas the forests cannot regenerate that biomass, even over hundreds of years.
Conclusion
Reed: Thank you, Dr. Poister for this thorough and very accessible presentation. It’s very helpful for all of us. We’ll be posting both the audio and the transcript notes on our website within the next couple of days. We’ll send it also to everyone who registered for this call. We have already had a series of calls starting on Saturday. The reports for the first three of those are available on our website under the news and updates ticker on our home page.
David: Thank you. And I just want to let everyone know, if you think of a question down the road, feel free to email me. Let me know how you know about me and I’ll be happy to help you out if I can.
Reed: We’ll happily include your email in the report! Barbara Kaufman has question.
Barbara: Hi and thank you Dr. Poister. I have a question for you about what we can personally do in terms of supporting the scientists. I don’t think I’ve ever seen science and scientists treated the way they have been in the last number of years. Is there anything we can do personally to support the science and the scientists?
David: Part of why I’ve been excited about doing presentations like this is because I think that quite a few people don’t understand the basic underlying facts of climate change. I’ve been recently talking to local groups. Northeastern Wisconsin is not necessarily a bation of liberalism. But on a number of occasions they have been a little surprised at how clear the evidence is that this is going on. I think that any time that you can reach out to people in a calm and rational tone and explain to them what’s going on, that’s beneficial. I hope that talks like this give you some information about how you can do that. Maybe point you towards those reports. Those things are very objective from a scientific standpoint. There’s no hyperbole there. They talk about not just what we think is going to happen, but also the confidence in those predictions. I think the facts are out there, and when you share them with people it points them in the right direction. Of course I’m a scientist so I think science is important, but I do think it’s relevant.
Reed: Tomorrow we’ll be talking at 9 am PDT with Sarah van Gelder of YES Magazine and she recently took a trip around what she calls the Edge of Change, not the coastal areas but places like Montana and Wisconsin to find out about where people are making changes about the way that they live and how that might affect climate. Along with her is George Price, a professor at the University of Montana on Native American and African American Studies, and we might get a sense tomorrow about that on the ground change that people are making. I invite you to join us for that!
David: that sounds great.
Reed: Thank you, one more time! I invite those of you listening, consider a donation to the CCI. These calls are always free, as are the reports and information. But our fledgling staff would like a little support to keep them going. So go to our donate page off of our website and give us either a small recurring donation or a onetime gift, whatever you can manage we appreciate. Thank you all, and have a good day!
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