Earth's Tipping Points - In-Depth with Dr. James Hansen, Director of NASA's Goddard Institute for Space Studies   Del 2
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Greetings, eco-friendly viewers, and welcome to today’s Planet Earth: Our Loving Home featuring leading climate scientist Dr. James Hansen. Dr. Hansen is the Director of the National Aeronautics and Space Administration’s Goddard Institute for Space Studies (GISS) at Columbia University, where he is leading the GISS in research on the planet’s atmosphere and global climatic change.

Dr. Hansen, like many of the more seasoned researchers of climate science, is increasingly concerned at what the studies are showing. These studies are based on three things: the Earth’s history, satellite data, and computer models.

The Goddard Institute for Space Studies has developed computer models to simulate the Earth’s climate from 1880 through to the present day. Dr. Hansen is quick to remind people that computer models are a useful tool, but cannot compare with the compelling truth told by the Earth’s past events.

This distinguished American scientist, leader and hero has received more than 20 awards, starting in 1977 with the Goddard Special Achievement Award.

On February 16, 2008, the American Association for the Advancement of Science (AAAS) honored him for his exemplary actions in helping foster scientific freedom and responsibility.

Dr. James Hansen had received the Shining World Hero Award from Supreme Master Ching Hai. For all his contribution and courage, the award was presented to him, “in recognition of boldly speaking the truth, generating worldwide awareness of the state of our planet, and advocating change to save our wondrous planet.”

For many years, Dr. Hansen has sounded the alarm on the worldwide threat of global warming.

Some of the tipping points to take note in relation to climate change include the melting of the Arctic ice sheets, extreme weather catastrophes and rising sea levels.  

Climate variability also has an impact on agriculture by causing severe drought in some regions and extreme floods in others.

The Tällberg Forum in Sweden is an annual event organized by the Tällberg Foundation. Recognizing the global interdependence of our modern society, the event offers leaders of the world a chance to exchange ideas and search for answers to the world’s challenges in an atmosphere of open exchange.

At the 2008 Tällberg Forum, Supreme Master Television’s correspondent interviewed Dr. Hansen on the seriousness of climate change.

Welcome to Supreme Master Television, Dr. James Hansen. It’s our great honor to meet you in person.

Dr. James Hansen (m):
My pleasure. Glad to be here.

Can you comment on what’s the situation now?

Dr. James Hansen (m):
It’s hard for people to realize this because you don’t notice much happening; the global warming is about one degree Celsius (1.8 degrees Fahrenheit), and weather variations are much larger than that from one day to another.

So you don’t notice that there’s a crisis, but in fact, we are at a crisis point now because we are very close to passing tipping points in the climate system that would have very undesirable consequences.

In fact, we’ve actually passed one tipping point, and that’s the Arctic Ocean. We’ve already reached a point where we’re going to lose all of the ice in the Arctic Ocean. Last summer, in 2007, about half of the ice in the Arctic melted.

The problem is that there are then positive feedbacks. A tipping point occurs where there are amplifying feedbacks that can come into play and cause large change to occur very rapidly.

And in the case of the Arctic, the way it works is that as ice melts, that exposes darker ocean, which absorbs more sunlight that causes more ice to melt.

And now, because the planet is out of energy balance, there’s more energy coming in from sunlight than there is heat radiation going out.

And the reason for that is that greenhouse gases, carbon dioxide and methane and other gases that we’ve added to the atmosphere trap the heat radiation.

So because of this energy imbalance, we know that the rest of that Arctic sea ice is going to melt, probably within five to ten years, maybe a little bit longer.

But, in any case, we’ve passed that tipping point.

Well that is a reversible tipping point.

If we were to reduce the amount of CO2 in the atmosphere so that the energy balance became zero or slightly negative, then the planet would cool off and the ice would come back.

But, what we’re concerned about is bigger tipping points, ones which are not reversible on any time scale that’s of interest to humans; for example, the ice sheets on west Antarctica and Greenland.

If those begin to disintegrate and slide into the ocean, then that’s irreversible on a time scale less than tens of thousands of years.

It takes a long time for an ice sheet to build up from snowfall. And the consequence of that, a sea level rise of several meters, would obviously be disastrous.

But another tipping point, which is also irreversible, is the extermination of species. We’re already putting pressure on species because temperature lines are moving, moving towards the poles at a rate of about 50 or 60 kilometers (31 to 37 miles) per decade. And the temperature lines are moving upward in the atmosphere.

So those species that are on mountains have to move to higher levels to stay within their climatic zone, or to higher latitudes. And, for some degree of movement, that’s not a problem, but as it happens faster and faster, we can cause many species to go extinct.

And then, the tipping point is when so many go extinct, they depend upon each other, you can cause ecosystems to collapse, and then you lose many species.

Obviously, we don’t want that to happen. That’s happened in the Earth’s history several times. There has been very large global warming, five or six degrees Celsius(9 to 10.8 degrees Fahrenheit) more than half the species on the planet went extinct and new ones came into being, but took hundreds of thousands of years.

Obviously, that’s a time scale we can’t even think about. So, we want to avoid those tipping points.

Have we passed any other point of no return?

Dr. James Hansen (m):
The point of no return is when you get to a place where the dynamics of the system takes over, and then you can’t do anything about it. It’s too late.

So if the ice sheet starts to slide down the slope toward the ocean, then it’s too late. You can reduce the greenhouse gases, but it’s not going to stop that ice sheet. We don’t want to get to a point of no return. I don’t think we are there yet, but in the case of the ice sheets, we may be getting close.

Because, if we go back to 1990, then Greenland was approximately in mass balance, we would have the same amount; it would get heavier during the winter as snowfall piled up, and then the edges would melt in the summer, and it was approximately in balance.

But it started to lose more mass in the summer than it gains in the winter. And last year, in 2007, it lost at least 250 cubic kilometers (60 cubic miles) of ice during the year. And that sounds like a lot, but it’s less than a millimeter of sea level.

But, altogether, the sea level is going up 3½ centimeters (1.4 inch) per decade; it’s affecting some island nations.

But the danger is that it could go up to a much higher rate, because we know that in the Earth’s history there have been times when sea level has gone up very fast, and we really don’t want to pass that point of no return.

So where are we now? What can we do now?

Dr. James Hansen (m):
In fact there are practical solutions. I think it’s important to point out that these solutions actually have many desirable characteristics.

It’s actually a brighter future beyond fossil fuels. The basic problem is burning the fossil fuels. We cannot burn all of the fossil fuels, all of the coal in the ground. Coal is the biggest contributor to this. If we burn all of that, put it in the atmosphere, the Earth would be headed toward the ice-free state, where it was when that carbon was in the atmosphere before.

We can’t let that happen. We’re going to have to move to energy sources beyond fossil fuels, and that actually has many advantages. So, for example, I think that we need to have, within the United States and within Europe and within China, we need to set up low-loss electric grids, which allow the energy from renewable energy such as solar power, wind power, to be transmitted long distances without losing the energy.

The current electric grids, alternating current grids, lose their energy pretty fast, so you can’t transmit it very long distances. But there is technology, a direct current high-voltage grid that could transmit energy long distances and allow renewable energies to take over in the long run.

And that has many advantages; first of all a cleaner atmosphere and oceans, reduce the air pollution. And it reduces the need for importing energy from places where you may be not confident of getting the energy on a long time scale.

And it preserves the planet, it preserves creation. So there are many positive things about solving the problem, and we could do that. But it does take leadership.

Does the government, are most of them doing something?

Dr. James Hansen (m):
The governments, they talk about reducing emissions by X%, the truth is, we’re going to have to reduce carbon emissions by approximately 100% because the carbon dioxide that we put in the atmosphere will stay there, much of it, for more than a thousand years.

Dr. James Hansen (m):
We just simply cannot burn all these fossil fuels and put the CO2 in the atmosphere. Governments think they can make small changes and maybe that’ll be good enough.

But it won’t. It’s become very clear that we’re going to have to have dramatic changes.

So, the policymaker has to make decisions quick now?

Dr. James Hansen (m):
Yes, we’re really running out of time.

In fact, I think this next year or two years are the critical time period.  With the need for an international agreement to follow the Kyoto Protocol, this is the time that we have to make major direction-changing decisions.

Part 2

If we follow the pace that we are going now, will there be disasters soon?

Dr. James Hansen (m):
Yes, we need some transformative changes.

So, what I would hope is, for example, that the United States would announce a project like a low-loss national grid, electrical grid. And say, “We’ll do this within a decade.” And it could be done. And it would allow us to wean ourselves off of fossil fuels.

So, what they’re talking about is CCS (Carbon Capture and Storage), like capture the carbon is not really working.

Dr. James Hansen (m):
Well, carbon capture and storage, burning coal at power plants where you capture the CO2 and store it underground.

Frankly, my suspicion is that once we explore all the options, that’s probably not the best one because you still emit mercury, which is a pollutant.

And you still have regional pollution due to mountain top removal and pollution of streams.

And coal is a finite resource. So, it might last most of the century, but it’s not an infinite supply.

In the newspaper, I think it was the 23rd of June, they talked about “Remember #350, the rest of your life!”

What does this have to do in terms of climate change?

Dr. James Hansen (m):
350 refers to the amount of CO2 in the atmosphere.

Now, during the Holocene, the last 12,000 years, CO2 was about 280 parts per million. Now, humans by burning fossil fuels, have increased that to 385. And it’s headed toward higher levels. It’s increasing about 2 each year.

Well, we’ve realized that we’ve gone too far. We’re going to have to reduce CO2, back to at least 350 and probably even lower.

But the point of 350 is that it’s lower than what we are now. So, the policies that we’re going to need in order to get there would be the same if it turns out that the optimum level is really 325 or 300 or 280. Then, we’re going to have to go through 350.

So the point is just to make people realize that we’ve already one too far.

So, all these disasters around the world are absolutely connected to the climate crisis?

Dr. James Hansen (m):
Well, you can’t say that all disasters in the world are connected to climate disaster, but what you can say, is that global warming increases the intensity of both extremes of the hydrologic cycle, the water cycle.

So, at the times and places when it’s dry, a stronger greenhouse effect means that you get stronger drying and higher temperatures, more extreme drought and as a result more widespread forest fires.

But, on the other hand, the other extreme of the hydrologic cycle also gets enhanced, because as the atmosphere gets warmer, it holds more water vapor. At a very strong rate, the amount increases with temperature, and therefore when it does rain, there’s a possibility of much heavier rains.

So, we get, not all the time, but we get some much stronger rainfalls and therefore heavier floods.

And so, that these on a statistical basis, we can see both of these things are happening. Without any doubt they are both happening.

And in fact, where I live, near the Delaware River, we’ve had -two hundred year floods in the last ten years.

And where I used to live in Iowa, we’ve had two 500-year floods in the last 15 years.

And I think that although you can’t blame a specific flood and say, ok, this was caused by greenhouse effect.

But, the frequency with which these happen and the severity of them is definitely affected by global warming.

Today on Planet Earth: Our Loving Home, Supreme Master Television features an interview with Dr. James Hansen on more effective actions in halting climate change.

We have heard this speech from the IPCC, climate change panel. And they won the Nobel Prize together with Al Gore.

IPCC Chief Dr. Pachuari said, “If the government is moving too slow, at least for the average people, individuals, the simple thing to do is eating less meat, ride a bicycle or be a frugal shopper,” or these kinds of simple steps.
What do you say about his?

Dr. James Hansen (m):
Well, sure. The things that individuals can do are helpful.

And one of the most helpful is actually a vegetarian diet, that produces much less greenhouse gases than a meat diet.

But because individuals cannot solve the problem by themselves, they’ve got to have leadership because we’ve got to change policies.

We need things like electrical grids.

There are many things that only can be done with leadership.

We have to have changes in rules like energy efficiency of vehicles and building efficiencies and utilities right now make more money if they sell you more energy.

That’s not the way we should set up the rules for utilities.

We should change it such that, if they help us save energy, save greenhouse gases, then they can make more profit.

There are a lot of things that only the government can do; the individuals cannot make those changes.

So, the individuals, what can you recommend them to do?

Dr. James Hansen (m):
There are many places in the US, in Germany and England, where citizens are starting to object to plans for new coal-fired power plants.

That is extremely valuable for citizens to do that.

And also, they’ve been able to block the drilling for oil in places like the Arctic National Wildlife Refuge and offshore of some of the states, on public lands.

And that’s also very helpful, because it simply doesn’t make sense to try to get every last drop of oil out of the ground.

We need to get off of our addiction to oil, and get onto clean sources of energy.

And there are a lot of publications that are saying that it is already available, for a long time, this kind of clean, sustainable energy.

Dr. James Hansen (m):
Well, clean energies are available, but so far, they are a small part of the total.

But some of them are close to being able to do a big part of the job.

Solar thermal for example, where sunlight is concentrated by means of mirrors and used to heat a fluid, and then drive an electrical generator.

That now works well enough that you can make a power plant that uses solar energy.

In fact, in the United States, there’s enough energy in the southwest desert to provide electricity for the entire country, but you would need an electrical grid to do that.

At the same time, there’s a report that says, from the U.N. agricultural, that raising animals for food causes more greenhouse gases than all transport.

If people turn to vegetarianism, and then to push the government and policy makers.

Dr. James Hansen (m):
Yeah, I think pushing the government and policy makers is the most important thing, and include pushing them not only by voting, but also by opposing things which are obviously bad policy.

Dr. James Hansen (m):
Well, I think we should not only emphasize the problem, but the fact that the solution has many great characteristics: clean atmosphere, renewable energies, and preserving creation, the planet that we have had for the last several thousand years.

How much time do we have left to make the action and to reverse the situation or at least stop the crises?

Dr. James Hansen (m):
How much time do we have left?

Well, I said two years ago that we had ten years, but I meant ten years to get on a different path. That means we have to start changing direction now. Because of the Kyoto Protocol expiring, it really means in the next year or year and a half, we really need to get on a different path.

Thank you very much, Dr. Hansen. It’s a great pleasure, and thank you for your noble effort. Wish you the best!

Dr. James Hansen (m):
Thank you.

Once again, we express our deep appreciation to Dr. Hansen for sharing his expertise and acknowledging that the vegetarian, meaning animal-free diet is one of the single most effective ways individuals can reduce their greenhouse gas emissions.

May his planet-saving work continue to bring awareness to public on the urgency to carry out actions to regain the balance of our ecosystem.