The Global Environment: Critical Issues for the Next Century - Henry W. Kendall Memorial Symposium at MIT (2/5)

[MUSIC PLAYING]

MODERATOR: As Tim was talking, I was thinking about the many conversations that we had with Henry about some of the great human puzzles to these problems.

Why is it that when Americans are polled about many of the issues that Tim was addressing, they are supportive of the kind of strategies and approaches that Tim outlined, and yet we cannot get the public policy alignment in place? It's a huge problem, and it's one that we need to continue to work on. And it's one that always mystified Henry, because he kept hoping that our elected officials would be rational.

[LAUGHTER]

I put this in one of the big issues he worried about. And indeed, perhaps understanding the science behind some of these big issues may be easier than understanding the human behavior that guides some of the people who are responding to that science. Today we're going to be looking at three big issues that Henry focused on in greater depth-- biodiversity, for which we need a new name; climate change; and arms control.

We begin with the as-yet-to-be-named biodiversity problem.

[LAUGHTER]

Ed Wilson is known to all of us. In addition to being a film star--

[LAUGHTER]

--he is the world's foremost authority on biodiversity. I know him as one of my daughter's teachers at Harvard and as the person who comes first to mind when, deep in the rainforest, I see a parade of leafcutter ants crossing the path in front of me. Do you really want everybody who goes into the rainforest and sees an ant to think of you, Ed? Well, we do.

[LAUGHTER]

You know his books on human nature and the ants, both of which won Pulitzer prizes and [INAUDIBLE]. The list of medals would take up the time for a speech, so with no further ado, I introduce Ed Wilson.

[APPLAUSE]

WILSON: Thank you so much. Thank you, Adele, and thank you also for the privilege of allowing me to join in this tribute to Henry. I had the privilege of knowing Henry Kendall only for a relatively short time. Some of you have known him for virtually a lifetime. After he asked me to help him add natural ecosystems and biodiversity to the environmental crusade he was spearheading under the aegis of the UCS, he was indeed--

MODERATOR: Are some people having trouble hearing in the back?

AUDIENCE: Yes.

AUDIENCE: Yes.

WILSON: Oh.

MODERATOR: Okay.

WILSON: I had trouble hearing you as well, so how is it now?

[LAUGHTER]

Which probably saved me from wincing a few times. Is this coming on okay now? Is it all right?

AUDIENCE: I think so.

WILSON: Is it better? It needs to be up. I should speak more loudly then, right?

AUDIENCE: Yes!

WILSON: Okay. I'm not sure whether the trouble is in the room or if it's in the sound system. I hope maybe we can get an increase in the volume of the sound system. Is that better?

AUDIENCE: Yeah.

WILSON: Is that coming okay?

[LAUGHTER]

All right. Begin again. This room is filled with MIT-- or I should say-- yeah, MIT know-how and Harvard technology.

[LAUGHTER]

Oh, I had to-- I do repeat myself somewhat. I had the privilege of knowing Henry only for a short time when I joined his crusade under the aegis of the UCS. He was indeed a brave, an honorable, and far-sighted, and a thoroughly admirable man. And I regret that I did not get to know him for years more. He will be greatly missed.

He knew and we now fully understand, as so splendidly expressed by Tim Wirth, that scientists and, with him, everyone else are entering what can be called fairly the century of the environment, which, in a nutshell, is that period in which humanity has got to get settled down before we wreck the planet.

Now, in the first slide, which I hope will come on-- there we are. Good. Today, as clearly and concisely as I can, as Henry would have liked it, let me present a picture of the status of biodiversity most relevant to the total environment, as we are addressing it this morning.

I'll start by putting a twist on it by placing biomass and biodiversity in some perspective. And here we have, representing the relative biomasses of ants representing the invertebrates, the little things that run the earth, as I like to say, with the vertebrates.

As important as they are, the ant biomass alone in the Amazon rainforest-- and this is true of most terrestrial environments around the world-- the ant biomass, the total weight of ants alone, as just one invertebrate group, is approximately four times that of all of the vertebrates together-- the mammals, and the birds, and the reptiles, and the amphibians.

Moreover, we should keep in mind as we enjoy and understand better the charismatic species on the minds of all, that there is, beneath them in the energy pyramids and biomass distributions, a great mass of species that form the bulk of the ecosystems. And these species are indicated here in total global biodiversity. This is both terrestrial and aquatic and marine. And here you see that the insects and the flowering plants dominate terrestrial and aquatic biodiversity of the world.

But primarily, because actually 90%-plus biodiversity of terrestrial systems, which is so overwhelmingly rich in biodiversity that the global picture is divided thus. And of the species that are thus represented, we can see perhaps more graphically in this cartoon the species-scape. The number of species found in each of the major groups as represented by, proportionally, the size of a typical organism.

Thus, the insects, with more than half of the known species of organisms on Earth, looms like a Goodyear blimp above the tiny mammalian representative, the elephant there, there to represent the 4,000 species of mammals. And the mammals are sort of hidden underneath these large mushrooms that represent the 60,000 or so fungal species.

Now, the important point I want to make out of this, aside from suggesting that we always keep in mind what the full extent of life on earth and particularly the diversity is, is how little we know about the numbers of species and the full pattern of diversity on earth at this point.

We now have, know, and have named some 1 and 3/4 million species of plants, animals, and microorganisms. But the actual figure could be anywhere from a quite conservative 5 million, according to some estimates, to as high as 100 million. And the fact is that we do not know the number of species on earth to the nearest order of magnitude. We know more about the surface of Mars than we do about the living surface of this planet.

So part of the exploration that has to be done in biology in the next century is to complete the great [INAUDIBLE] enterprise and discover and map all of the biodiversity of the earth even as it is rapidly disappearing. And this takes me then to the tropical rainforest, where some half or more of all of the species of organisms are thought to live, by most specialists.

The tropical rainforests in black here covers some 6% of the land surface of the earth. That's down about 50% due to human activity. The rainforests, the great treasure house of the world, is also the least explored. And part of the reason is illustrated by this photograph of a graduate student at Harvard in Borneo, namely climbing up to the canopy, namely that so much of the biodiversity is concentrated in the canopy.

And yet that is one of the most difficult environments to get to. The trees tower often up to 100 feet or more, the top canopy trees. The bowl or trunks of the trees are relatively smooth and straight and do not put out their nearly horizontal limbs until near the top.

The bark is often spiny, if not smooth, difficult to climb. And up at the top in the branches, as you can see, up in the upper left-hand corner, are masses of epiphytes in the gardens, forming gardens there, orchids, and gesneriads, and bromeliads, and other species, as many as 50 or even 100 species may be found in the canopy of a single tree. And these are dense, full of spines, hard to climb through, and swarming with stinging ants, and bees, and wasps. And Tarzan would not have lasted 15 minutes.

[LAUGHTER]

Now, a great many ingenious methods are being developed to get up there. One of them is-- and of course, they include-- and this certainly must have warmed a spot in Henry's heart-- included rope climbing, standard rope climbing, rock climbing techniques to get up there. But also as illustrated here, the use of building cranes, as pioneered by the Smithsonian Tropical Research organization.

And it simply consists of taking a crane up to the edge of a rainforest patch, as in Panama, or down a path, a cut road into the rainforest. And then letting investigators move out on the end there and be lowered up and down the rainforest canopy and, in addition, rotated around. So this way, you can get an enormous volume covered. And here is the actual device in place.

And here is the gondola. Here is the gondola with a couple of botanists. And they are looking, seeing, and working at a spot which was not previously accessible, namely the outer foliage of the canopy. Too light to support a human. And not accessible in any other way from the land and from the ground.

So for the first time, they can get and look right at where the growth is maximally occurring and where a large amount of the biomass and biodiversity occurs that is least explored. They also have to be in cages up there with a door that can be slammed shut fast because of the Africanized or killer bees, which have spread now throughout the New World tropics. And one does not want to be dangling at the end of a crane arm in the middle of a canopy when you bump into a nest of those.

There we go. Now, the diversity of the rainforest is legendary. From this canopy of a single tree illustrated here, I identified some 46 species of ants living there and 23 genera. And that is about the same number of species of ants found in all of Europe. So this gives you living in one tree. So this gives you an idea of just how rich the tropical forests are, if I may maintain emphasis on them a bit longer.

In 1955, as a young biologist at Harvard, I set the world record for the largest number of ants found in a single square kilometer. I was in New Guinea, at 172. I know that was a world record, because it was the first time that was done.

[LAUGHTER]

Subsequently, a Brazilian entomologist put that right up over 200 in the Brazilian environment. And then a British entomologist shoved it on up to 250 or so, working in West Africa. And then a few years ago, I asked one of my graduate students and our curatorial assistant managing the ant collection to go down to the tropical Andes, to equatorial Peru, where I knew and others knew where possibly the richest, most biodiverse area in the world.

And I said, go down and break the record, and don't come back till you do this. No, I'm just kidding. I said this was part of a very important survey that I wanted done. And I said, well, you probably could break the record, which they did. And it still stands at 365 ants in about 20 acres.

So I could go on and on with stories of this kind, but must move on and emphasize that in spite of the proper stress on the tropical rainforest, which is being destroyed at an accelerating rate, we must not forget the other terrestrial environments which have richnesses distinctive to themselves and are also, in most parts of the world, under severe stress.

Right here at home, the temperate forest is surprisingly unexplored at the meso and micro levels. When we are in a forest and look down on the forest floor, we think we see a two-dimensional world. And that is, in a sense, correct, because we are among the largest organisms on earth. And we are rather like Godzilla walking through New York City. Everything sort of looks flat down there. But when you magnify the whole thing and-- let's see. Up.

Well, we are advancing regardless of a button I pushed.

[LAUGHTER]

Yes, thank you. I'm glad to see, in spite of the computer revolution and the prospects of petaflop-- in spite of petaflop computers in our near future, the human element is still needed. Thank you, sir.

At any rate, now we are a side view of this magnified many times, so that you see over a distance of only a few centimeters. And at once, you see this is a three-dimensional world. For the majority of the species of organisms, namely as you go from the top, with dry leaves, recently fallen, large spaces, a certain chemical regime, and high temperatures, and [INAUDIBLE] light millimeter by millimeter down through the leaf litter and into the humus.

And in stages, you are descending into different worlds of physical, chemical, and biological world, as though you were descending the ocean 10 meters at a time. And it is this enormous diversity in the natural ground of a [INAUDIBLE] system that provides a huge array of niches for every level in the trophic web. And this is what holds this ensemble, with its material cycles and balances of populations and so on that holds the natural environment into this steady state that we so desire to see it kept.

And the diversity here of small organisms. Here we have them for a single square foot roughly of Panamanian rainforest ground. It's quite staggering. Into the tens of thousands of individuals. And many hundreds of species in just a square foot.

And on looking at the environment scaled down in this way, we see that what is apparent as just a small fragment of the passing environment from the point of view of a flying bird or ourselves walking by is the equivalent of an island for some of the smaller organisms-- for most of the smaller organisms. And here is an example of how a rotting stump is, at different stages in the temperate forest, divided up among one particular group of organisms, a fly larvae, out of hundreds.

And so you can see that the microecology of any chosen group of smaller physical size is itself subject for a proper lifetime study. Many of these species would be undescribed even here in New England. One can spend a lifetime in a Magellanic voyage around one tree stump once you scale down size and an area in space in your studies.

What is biodiversity? I suggest that if we have to have a new name, as Tim Wirth thinks might be useful for public education, we might try "creation." But on the other hand, I think that the unfamiliarity of the word "biodiversity" comes less from its technological ambience than from the fact that to the importance of biodiversity and the magnitude of the environmental insult of species going extinct is much harder for the average person to understand than is the, say, polluting of a river or the rising of global temperature. So it's a matter more of education, and this is an area where scientists, in addition to research, and counseling, and activism, should be more fully engaged.

Biodiversity then is all of life. And it is made less than banal by recognizing biologists study it in horizontal sections, going from ecosystems as the main level in which diversity occurs to the species that compose it, as seen in this Australian example, down to smaller organisms and then beyond that-- the genic, or genomic, diversity within individual species. Yes.

And we should bear in mind that at that last level, the diversity becomes immense. A back-of-the-envelope estimate of diversity that takes into account the species, all the species, and all of the genes in them, and the possible genic variation that may occur, takes us to 10 to the 17 given order of magnitude of how much biodiversity there is in the earth at the present time.

In the case of DNA, many of you will recognize this as a panel showing the actual DNA molecules, a little micro spaghetti all through there, for a one part out of 4,500 of the total human genome. So if you just extended that on 4,500 times, each with a different part of the genome, you would get what's in a single cell.

Another way of putting it is to recognize that if we put all of the four DNA strands of a diploid nucleus from the human body end on end in real space, it would stretch for roughly one meter. But it would only be two nanometers across, so you wouldn't see it, even though you literally could hold that molecule and it would be that long.

However, if we could magically increase it in thickness until it was as thick as a piece of wrapping string, then we would get this kind of a ramping up, namely that our DNA molecule, now as thick as a piece of wrapping string, would extend to approximately 1,820 miles, or the distance between New York and Dallas. And as you walked along it through that distance, you would be reading off about 100 nucleotides an inch.

And that is worth bearing in mind, because the uniqueness of a species in that code is what we lose when we lose a species, not to mention what could be an important part of the ecosystem or not even that. Certainly, on average, a million years or more of genetic evolutionary history.

Oh, I did want to mention, as a personal note, about this route into biology, because it's worth noting, particularly this close to MIT-- that there is more than one way to go into science. And the nice thing about entering science as a naturalist, which was my ontogony, is that it is a lifelong occupation, that it can fascinate and can grip youngsters as early as they're-- well, as early as 9 or 10.

To acquire an affiliation with the natural world comes very easily for children, as I have always said. Every kid has a bug period, and the only thing different about me is I never grew out of mine. And so here I am as a 13-year-old in Mobile, Alabama, collecting insects. And here I am 50 years later.

[LAUGHTER]

Nothing changed, basically, except that I got a great job at Harvard doing this. And also, I guess my vocabulary grew. At any rate.

The other thing that happened along the way is what happened to so many of us now in the environment movement and to so many of those dedicated to the basic and applied studies of biodiversity, namely the recognition that the natural world is disappearing at an accelerating rate. The rainforests are disappearing at the rate of about 1% to 2% a year.

Just as an example, and certainly the most important single example, if the rainforest covers an area of 48-- they do cover an area of approximately equal to the 48 contiguous United States. And they are disappearing, being clear cut down to below 10% of cover at the rate of the area of Florida each year.

And of those remaining, as in the Brazilian Amazon, now that we are getting more finally resolved photographs and on-the-ground analyses, furthermore, those that survive are being cut into by trails that aren't so easily observed from the air. And other changes are occurring that are degrading and fragmenting the rainforest.

And here is the decline, for example, of one of the most beautiful and richest of all over 150 years or so. Almost-- yes, over 150 years. This is the state of Sao Paulo, and the black is the magnificent Atlantic forest, with a very distinctive fauna and flora. Down to way below 10% of what it was. Yes.

And we can see, as you saw briefly in the film shown at the outset, that the humanity is changing the whole surface quite visibly. This is the collage, or a composite, I should say, of photographs taken by the US Air Force Satellite Weather Monitoring Survey, showing how the world really looks at night if there were no clouds obscuring your view.

And you can see that the Eastern Seaboard of the United States is expected, in Europe, and incandescent Japan are all lit up, but also that there are a great many small pinpoints of light through less inhabited areas in the Brazilian Amazon. And then the Congo Basin and in the Sub-Saharan Desert. These are fires burning up the cut timber or rubbish left from it. And firing the grasslands of the drier areas. NASA estimates that 5% of the Earth's land surface is burned each year. Right.

And as the area of habitats decline, we know that there is a quite steady and predictable decline in the fauna and flora, the numbers of species. And this relation is illustrated here not by the physical decline of habitats, but the same thing applies, in the West Indies where the area uses that of the standing Antillean Islands from Cuba down to small islands like Redonda. We see that the number of species that stably exists there drops 50% for every 10-fold reduction in area. You lose 90%. You lose eventually half of the species.

This is well illustrated. And this is true of habitat islands as well as regular oceanic islands. And this is well illustrated by our national park system. Parks of the Western United States and Southwestern Canada are, in fact, islands in a growing sea of human habitation and other disturbed environments. And just as predicted by our worldwide observations of the pattern of biodiversity and by the theory of turnover of species developed by biologists, the faunas are spontaneously dropping.

Now let's see. I think I must have missed a-- there we are. Yes, this is the number of mammal species dropping, as it has dropped in parks overall in the last 100 years. Not all the mammal species will disappear, but there will be this continuous, autonomous, endogenous loss of species no matter how carefully the parks are protected. So this is a sobering aspect of the loss of diversity through habitat destruction. And yes.

This is the Nature Conservancy's latest report on the United States. Of 120,000 species we know, roughly, plants and animals, about 1% are certified extinct, and 30% are in varying degrees of endangerment. It is far worse than that in most of the developing countries. But I thought I would bring it a little closer to home to show you that right here we are suffering the same amount of stress. The red states, which include Hawaii, and California, and unfortunately, my native state of Alabama, are among those in which the species extinction and shift to vulnerability is maximal.

Now, I will conclude this by showing you the faces of extinct and endangered species, because it is my conviction that only by coming to know these species as individuals, as entities, million-year-old entities that we have inherited, that are part of our lives and our environment, only by coming to know them as individuals can we expect the public to care about whether they will be preserved.

Otherwise, they just become statistics. And people might be very willing to live with 20% or 30% or 40% fewer species on Earth if they know nothing at all else about what this is doing to us and know nothing at all about what these species are.

So here are the portraits of several. The cerulean paradise flycatcher of Indonesia, newly extinct.

The golden toad of Costa Rica only discovered a few decades ago, on its way to becoming the national symbol of Costa Rica's natural history, extinct within the last several years.

The Hawaiian honeycreepers-- this magnificent explosion of species that occurred over a couple of million years in the Hawaiian archipelago-- now extinct to the level of 75%, with most of the other species hanging on by a thread. Several critically endangered.

The Hawaiian abandoned snails, tree snails, half extinct. The others endangered.

The Tennessee coneflower, endangered. Macfarlane's four-o-clock, endangered. The sword of Hawaii, endangered, but fortunately, under strict protection.

The world's most endangered species, a cook's [INAUDIBLE], a magnificent flowering shrub that once covered a whole Hawaiian island, now existing only as tin implants into stocks of other species. They don't even have enough genetic capacity to germinate as they exist today, so they're just hanging on in that respect.

So I will conclude by saying, looking at this slide, which shows the five great extinction spasms of the past 450 million years that have been worked out by paleontologists, caused, at least in the last case, the one that closed the Mesozoic 65 million years ago by the massive bolide strike at the Yucatan Peninsula.

And under research and discussion as to what the main cause is is under research and discussion for the others. But it's happened very roughly about every 100 million years in the time of Earth's history-- that large organisms have flourished and have invaded the land. And now we are in the midst of the sixth great extinction. We are in the early stages of it.

And the question is, are we going to let it happen in full sight as part of the degradation of our ecosystem, of the ecosystem services, of all that biodiversity can provide us in the way of new products, of new ideas, of new scientific knowledge, in the view of the ethical concerns that preserving the rest of life on Earth, of the creation should be a primary ethical precept. In view of all this, will we let it go on? Will we let it become the sixth great extinction in the history of life?

The natural world is indeed endangered, but it is not too late to make a big difference. We're going to lose a lot of biodiversity, as you saw happening at least locally in the case of the national park. But with exact knowledge and desire, we can help to slow and eventually stop the hemorrhaging.

Right now the world population is just past officially 6 billion and will go to somewhere between 8 and 10 billion by mid-century and hopefully peak, with a little bit of luck. And we, humanity, have to hope-- we have to believe that our species is going to pass through this bottleneck of overpopulation and the thrusting upward of the developing countries to attain a decent standard of living in such a way that we will come out overall as a species better off than we started.

But we hope. We have to have, I think as a moral imperative, that in so passing through it, we will not destroy any more of the natural environment and the species diversity than is necessary and not allow any more than we can possibly prevent.

We should try to carry as much of life through the bottleneck as we can. We must do what we can to save the creation and not to push the rest of life off the face of the earth. We should remember that, along with culture itself, that inheritance will be the most precious gift that we can give to future generations. Thank you.

[APPLAUSE]

MODERATOR: Thank you very much, Ed. I did want to assure you that when I'm in the rainforest and looking at leafcutter ants, I think of you, but not when those little red ones come and sting me.

Ted Sizer, who is my mentor in educational matters as much as Henry was on many other matters, always said that when he was teaching, what he wanted always to be able to do was to say to people every 45 minutes, stand up and stretch. So this is not a coffee break, but if you want to stand up for 30 seconds, and stretch, and whatever, we're going to come back and then move on to another talk.

[SIDE CONVERSATION]

Okay, folks. That's it. [LAUGHS]

PRESENTER: The lighting is terrible. This searchlight is only meant for the speaker here. That's all. And is Watson showing slides also?

MODERATOR: I don't know. Where is he?

PRESENTER: Is Watson showing slides?

PRESENTER: No, he's [INAUDIBLE].

PRESENTER: Okay, that was [INAUDIBLE]. So they should turn that off now.

MODERATOR: Okay, well--

PRESENTER: They should have just had a standing lamp here.

MODERATOR: Where is Bob?

PRESENTER: I don't know where he is.

MODERATOR: There he is. Okay. We're reconvening. A chemist by training, Bob Watson has devoted most of his professional life to shaping and strengthening the international institutions that have an environmental impact and that indeed determine the international agenda in dealing with these issues.

He is currently Director for the Environment and Head of the Environmental Sector Board at the World Bank. He also helped shape and establish the Global Environmental Facility, which is a central part of the World Bank's environmental work.

One of the areas that Bob is focused on is climate change. And I hope all of you had a chance to see the Wall Street Journal article this past Tuesday, which was buried in their second section, but it was an extraordinary cover section devoted to climate change.

If it isn't all of your daily reading, try to find someone who can give you a copy of it. It's even better than taking it off the website because of the graphics that they used. It's quite wonderful to have indeed this issue receive the kind of coverage that the Journal gave it just this week. Indeed, that's something that I think would have pleased Henry a great deal.

But getting governments to agree and to work together around the issue of climate change is no small matter. Getting the scientists to agree on the science part of it is an essential piece of getting the government's agreement and laying the basis for international action.

As Chair of the Intergovernmental Panel on Climate Change, Bob has been working to make this happen and will continue to do so. He has received many, many awards and continues to be very active in a full range of international institutions. But today we're asking him to address the issue of climate change. Thank you very much, Bob.

[APPLAUSE]

WATSON: Thank you. It's a real honor to be invited here to talk at this particular occasion. [INAUDIBLE] for probably about four years, first when he organized a major meeting at the World Bank. I was working at the White House at the time. In that very short span of time, I worked with Henry on climate change issues, biotechnology, and biodiversity.

In fact, my very last conversation with Henry was indeed how to get the public to understand biodiversity. [INAUDIBLE] meeting in Paris. He felt very passionately that we were starting to get the message across on climate change, but unfortunately, we had yet to get the message across on biodiversity.

AUDIENCE: The mic is not yet working. Maybe--

WATSON: Okay, is it now? Yes. I've learned I can speak to an audience even this large often without a mic. Let me give you-- however, I've been asked to talk about climate change. But let me first say-- and I think this is how Henry would have started this-- Henry cared about people, the environment, and science and technology. The challenge we've got in reality is how to alleviate the poverty that's pervasive in this world.

As Tim Wirth said, a quarter of the world's population lives on $1 a day. That's actually the cost of my hotel room last night here. Half the world's population lives on $2 a day. That would be two nights at this hotel. Nearly a billion people are currently malnourished.

1.3 billion people live without clean water, 2 billion people without sanitation. 2 billion people live without electricity. Between 1 and 1/2 and 2 billion people live with either indoor air pollution or outdoor air pollution. 5 million children die of waterborne diseases or air pollution each year. All of it avoidable.

The problem is, as we try and meet one of the basic human needs of food, something Henry felt passionately about, with perturbing our environment. As we use excessive nitrogen fertilizers, we're starting to contribute to climate change. And as the climate changes, it makes it harder to meet food supply, especially in the tropics.

As we extensify-- in other words, we cut down more forests, more land for agriculture, we're destroying our forests, we fragmentate the habitat, we lose biodiversity, the ecosystem species, and genetic level. And as we lose it at the genetic level, it once again threatens food supply. And if we use irrigation unwisely, in many cases, it leads to salination of the soils, land degradation, and once again, we threaten food supply.

So with the current practices that we try and meet the basic demand for food, we're destroying our environment. And as we destroy our environment, it makes it much harder to meet that basic human need in the first place. We currently have six major global environmental issues, all connected to local and regional environmental issues-- climate change, loss of biological diversity, land degradation, stratospheric ozone depletion. For these first four, we have global conventions and the world is, to some degree, trying to get to grips with these.

We also have principles enunciated in Rio on forestry and fresh and marine waters. One of the problems is even though both the scientific community and the political community have realized these are key issues-- and I've put a seventh, persistent organic pollutants, which is also a global issue-- we treat them in isolation. And in reality, they're highly coupled.

As we change climate, we change the structure and functioning of ecological systems, and we change the ecological systems at the ecosystem, species, and genetic level. And as we change biodiversity, we change the biogeochemical cycling of the earth, the exchange of chemicals and energy between the atmosphere, the ocean, and the land.

As we change climate, we change the temperature structure of the atmosphere that affects the rate of stratospheric ozone depletion due to chlorine- and bromine-containing compounds. And as the chlorine- and bromine-containing compounds destroy ozone, it changes the temperature structure that again feeds back on climate.

Strong links also between climate, desertification, water, and forestry. The challenge we have is to understand these scientific linkages and the policy linkages, to identify the win-win solutions and to recognize the trade-offs. Unfortunately, at the moment, we tend to look at these in splendid isolation.

The key question is, what are the underlying causes? They're basically the same independent of which issue you look at. These are not in an order of priority. It's population growth, as Tim Wirth has already talked about. It's increased demand for biological resources and energy as a function of economic growth and population growth. And as Tim also said, it's primarily consumption patterns in the north, but exacerbated and will be exacerbated by population growth primarily in developing countries.

The inappropriate use of technologies. Even after we understood that chlorine- and bromine-containing compounds were destroying ozone, we still carried on using them for a decade or more. Even now as we understand that the burning of fossil fuels is leading to local air pollution, regional acid deposition, and global warming, we continue to use fossil fuels.

We have to recognize that the markets do not work. They do not recognize the value of natural resources. There are no markets for pollination services, for water purification, for cleaning the air. And even if we could make the markets work, the challenge will be to appropriate the global value down to the local level, to the landless peasant.

We have to recognize that when we don't internalize the social costs of most of our actions, the price of coal does not include the environmental damage to human health or ecological systems. If it did, it would be much more expensive, and it would allow for energy efficiency and renewable energies to be competitive on the world's markets.

We have to recognize our both institutional and government failures. We understand about fisheries, but fisheries are collapsing around the world, mainly because we don't enforce those very regulations that were based on reasonably sound science. And unfortunately, most people don't look ahead. They don't care about their children, grandchildren, less alone the generations to come.

But I wasn't asked to talk about that. I was asked to talk about climate change. The issue is, very simply, as we produce energy from burning of fossil fuels, coal, oil, and gas, as we deforest the tropics, we put more greenhouse gases into the Earth's atmosphere. As we put more greenhouse gases into the Earth's atmosphere, we believe we are indeed changing the Earth's climate.

This figure shows the CO2 emissions over the last 140 years. And they're growing continuously. As I say, due to energy policies and land use policies, an atmospheric concentration of CO2 is going up. The background concentration of CO2 at the beginning of the Industrial Revolution was around 280 parts per million. Today it's 360 parts per million, a 25% increase.

Is it easy to understand the climate system? No. First, we have to understand human activities. We have to understand population. We have to understand economic growth. We have to understand the availability of energy. We have to understand how research and development may change energy technologies.

We have to understand the policy formulation process of how those energy technologies will penetrate the marketplace. We have to understand the natural forcing of the Earth's system, changes in solar radiation, changes in volcanic activity. And within that, we have to understand the interplay between the physical, chemical, and biological system.

What would we predict, though, from theory, would happen with more greenhouse gases? First, there should be an increase in temperature. More in winter than in summer. Two, there should be more precipitation, especially in winter. Third, very, very iffy issue, this one, reduction in the Asian monsoon precipitation. We expect longer-lasting droughts, especially in summer. We'd expect nighttime temperatures to increase more than daytime temperatures. And we'd expect more heavy convective rainfall. We are actually observing all of these.

There's this temperature for the last 100 years. The red spots show areas where the temperature's increased. The mauve spots, which is only five on there in total, I think, show it's decreased. Literally, the Earth's mean surface temperature has increased. This green line is indeed the temperature increase over the last 100 years. It's increased about 0.6 degrees Centigrade on average. The land surface temperature is about 0.8. And the ocean's about 0.4.

Is it consistent with theory? The simple models clearly don't try and simulate all the bumps and wiggles, which are due to changes in solar output, volcanic eruption, and the natural exchange of energy between the atmosphere and the ocean. But the model is basically consistent with a theory that suggests in a double-CO2 world, the Earth's mean equilibrium temperature will increase three degrees Centigrade. Doesn't sound a lot, but if you remember the last Ice Age was only five degrees cooler than it is today. So three degrees Centigrade is a very significant change.

If, however, we took a more sophisticated model and look at the change of temperature as a function of latitude, the equator here, South Pole, North Pole, close to the Earth's surface, and close to the [INAUDIBLE], 10, 15 kilometers above the Earth's surface. And we had the model only had greenhouse gases, we would predict the Earth would become warmer. It would become warmer, basically, to date, by about 1 to 2 degrees Centigrade. These are the observations over the last 25 years.

And as you can see, the observation suggests warming in the southern hemisphere, less warming in the northern hemisphere, cooling up high. So the CO2 model isn't exactly perfect. It doesn't show the interhemisphere asymmetry.

If, however, we also allow that when you burn coal, you also put sulfur dioxide into the Earth's atmosphere, which becomes, actually, the formation of acid deposition, you effectively get a cooling in some parts of the Earth. And what happens is there's an offset of the CO2 warming in the northern hemisphere due to the large amount of sulfur dioxide putting by burning fossil fuels in the northern hemisphere.

Now when you compare this calculation to the observation, you see the interhemispheric asymmetry, and to a first degree, the actual magnitude of the projected climate change is similar to what we've actually observed. You could say that we haven't got the transition between warming and cooling correct between the models. But there's a more sophisticated slide that shows taking into account stratospheric ozone depletion, the transition between warming and cooling becomes almost perfect. Okay.

Now the question is, what's likely to happen in the future? Depending on what population increases you predict, depending on what you believe will happen to energy prices, economic growth, we believe atmospheric emissions of CO2 will increase. We believe atmospheric CO2 could increase from 360 parts per million today to somewhere between 500 parts per million and 1,000 parts per million. In other words, by 2100, even the optimistic scenario would be a doubling of pre-industrial CO2. And otherwise, it could even be tripling or quadrupling.

What would that mean? A one- to three-and-a-half-degree Centigrade increase in temperature. Even the lower level would be a rate of climate change faster than anything observed in the last 10,000 years.

Is the temperature increase uniform? The answer's no. Land surfaces warm more than oceans, and the polar regions warm more than mid-latitudes. This is a projection for the 2050s. If you look at Africa or Latin America, one's projecting a four- to five-degree temperature increase in only five decades. The oceans are not warming as much. And the high Arctic is warming probably equal to Africa and Latin America. So we see very, very large changes in temperature, especially in these particular areas.

And that's what I wanted to focus on in part of my talk. Have we seen a change in precipitation? The answer's yes. It doesn't take a rocket science to work out if you warm the oceans, you get more evaporation. Hence, you should get more precipitation. The question is, where and when? What we see in the green spots are parts in the world where it's become wetter. And the red is where it's become drier. Please note the southern part of Europe, the northern part of Africa, and the southern parts of Africa have all become drier in the last 100 years.

Theory's suggested that we should get more precipitation in winter. This is the United States. And as you can see, in the last couple of decades, there has indeed been an increase in precipitation in winter. Theory also suggested that there should be more heavy precipitation events.

This, again, is the United States. The definition of a heavy precipitation event in this particular analysis is two inches of rain within 24 hours. And what you see is indeed an increase in precipitation, in heavy events. There's also another slide which complements this, which is, what's happened to light precipitation events? And they've actually decreased in the United States.

What this actually leads to is in an area which has a no change in annual precipitation, one would have both more floods and more droughts in the same place. A very perverse outcome. This is the projection for rainfall precipitation in the 2050s. Look what the prediction is for Africa. Northern Africa, Southern Europe through to the Middle East, and Southern Africa projected to be drier. If we'd assimilated backwards for 50 years, it would have been exactly the same pattern.

If you remember the pattern I showed earlier of precipitation changes across the world, it's exactly this pattern. When I say "exactly," it broadly matches. It's not a perfect match. There are inconsistencies, but the picture is fairly solid. It's this type of information that Tim Wirth referred to when the IPCC says it is now a discernible human influence on the Earth's climate system.

The things to note are indeed the areas where it's projected to get drier. That is to say through Africa, the Middle East, and the southern parts of Africa.

One of the key questions is, will there be more hurricanes or not? This has been a very contentious issue. The observational record of the last 100 years for the United States shows there has been no change in either the frequency or the magnitude of hurricanes hitting the United States. This also suggested, from the theoretical models, that we don't know if it will change in the future. Some models do suggest an increase in the frequency and magnitude of hurricanes. Others don't. But the observational record today says no significant change in the hurricanes hitting the United States.

One of the real questions that we have to ask ourself is, will the flow of energy and the circulation of the oceans change? This is a schematic of Wally Broecker showing-- and I won't go into details-- that there's basically an ocean conveyor belt that runs around the Earth. And in particular, the key area is off of Greenland in the North Atlantic, where there is a downwelling of water from the Earth's surface down into the depths. It's the way the ocean circulates, and it comes back in deep water.

One of the questions is, in a warmer world, can we stop the ocean circulation? If so, there would be tremendous changes in the Earth's climate in all regions of the world. Why could you conceivably change the ocean circulation belt? Very simply. At the moment, the water off Greenland is very cold and very, very saline. And it sinks. In a warmer world, the temperature would go up, so it's got less reason to sink.

But even worse, the Greenland Ice Belt, or ice sheet, could also melt, making it less saline. So in two reasons-- it'll become less saline, less cold, it won't sink. Is there any theoretical observation to say this is likely to occur? This is a little model put together by the British Met Office. They actually went back 100 years. The black line is what they ran the ocean circulation model for about 200 years.