Last year I showed these two slides so that demonstrate that the arctic ice cap, which for most of the last three million years has been the size of the lower 48 states, has shrunk by 40 percent. But this understates the seriousness of this particular problem because it doesn't show the thickness of the ice. The arctic ice cap is, in a sense, the beating heart of the global climate system. It expands in winter and contracts in summer. The next slide I show you will be a rapid fast-forward of what's happened over the last 25 years. The permanent ice is marked in red. As you see, it expands to the dark blue -- that's the annual ice in winter, and it contracts in summer. The so-called permanent ice, five years old or older, you can see is almost like blood, spilling out of the body here. In 25 years it's gone from this, to this.
This is a problem because the warming heats up the frozen ground around the Arctic Ocean, where there is a massive amount of frozen carbon which, when it thaws, is turned into methane by microbes. Compared to the total amount of global warming pollution in the atmosphere, that amount could double if we cross this tipping point. Already in some shallow lakes in Alaska, methane is actively bubbling up out of the water. Professor Katey Walter from the University of Alaska went out with another team to another shallow lake last winter. Video: Whoa! (Laughter) Al Gore: She's okay. The question is whether we will be.
And one reason is, this enormous heat sink heats up Greenland from the north. This is an annual melting river. But the volumes are much larger than ever. This is the Kangerlussuaq River in southwest Greenland. If you want to know how sea level rises from land-base ice melting this is where it reaches the sea. These flows are increasing very rapidly. At the other end of the planet, Antarctica the largest mass of ice on the planet. Last month scientists reported the entire continent is now in negative ice balance. And west Antarctica cropped up on top some under-sea islands, is particularly rapid in its melting. That's equal to 20 feet of sea level, as is Greenland.
In the Himalayas, the third largest mass of ice: at the top you see new lakes, which a few years ago were glaciers. 40 percent of all the people in the world get half of their drinking water from that melting flow. In the Andes, this glacier is the source of drinking water for this city. The flows have increased. But when they go away, so does much of the drinking water. In California there has been a 40 percent decline in the Sierra snowpack. This is hitting the reservoirs. And the predictions, as you've read, are serious.
This drying around the world has lead to a dramatic increase in fires. And the disasters around the world have been increasing at an absolutely extraordinary and unprecedented rate. Four times as many in the last 30 years as in the previous 75. This is a completely unsustainable pattern. If you look at in the context of history you can see what this is doing.
In the last five years we've added 70 million tons of CO2 every 24 hours -- 25 million tons every day to the oceans. Look carefully at the area of the eastern Pacific, from the Americas, extending westward, and on either side of the Indian subcontinent, where there is a radical depletion of oxygen in the oceans. The biggest single cause of global warming, along with deforestation, which is 20 percent of it, is the burning of fossil fuels. Oil is a problem, and coal is the most serious problem. The United States is one of the two largest emitters, along with China. And the proposal has been to build a lot more coal plants.
But we're beginning to see a sea change. Here are the ones that have been cancelled in the last few years with some green alternatives proposed. (Applause) However there is a political battle in our country. And the coal industries and the oil industries spent a quarter of a billion dollars in the last calendar year promoting clean coal, which is an oxymoron. That image reminded me of something. (Laughter) Around Christmas, in my home in Tennessee, a billion gallons of coal sludge was spilled. You probably saw it on the news. This, all over the country, is the second largest waste stream in America. This happened around Christmas. One of the coal industry's ads around Christmas was this one.
Video: ♪♫ Frosty the coal man is a jolly, happy soul. He's abundant here in America, and he helps our economy grow. Frosty the coal man is getting cleaner everyday. He's affordable and adorable, and workers keep their pay.
Al Gore: This is the source of much of the coal in West Virginia. The largest mountaintop miner is the head of Massey Coal.
Video: Don Blankenship: Let me be clear about it. Al Gore, Nancy Pelosi, Harry Reid, they don't know what they're talking about.
Al Gore: So the Alliance for Climate Protection has launched two campaigns. This is one of them, part of one of them.
Video: Actor: At COALergy we view climate change as a very serious threat to our business. That's why we've made it our primary goal to spend a large sum of money on an advertising effort to help bring out and complicate the truth about coal. The fact is, coal isn't dirty. We think it's clean -- smells good, too. So don't worry about climate change. Leave that up to us. (Laughter)
Video: Actor: Clean coal -- you've heard a lot about it. So let's take a tour of this state-of-the-art clean coal facility. Amazing! The machinery is kind of loud. But that's the sound of clean coal technology. And while burning coal is one of the leading causes of global warming, the remarkable clean coal technology you see here changes everything. Take a good long look: this is today's clean coal technology.
Al Gore: Finally, the positive alternative meshes with our economic challenge and our national security challenge.
Video: Narrator: America is in crisis -- the economy, national security, the climate crisis. The thread that links them all: our addiction to carbon based fuels, like dirty coal and foreign oil. But now there is a bold new solution to get us out of this mess. Repower America with 100 percent clean electricity within 10 years. A plan to put America back to work, make us more secure, and help stop global warming. Finally, a solution that's big enough to solve our problems. Repower America. Find out more.
Al Gore: This is the last one.
Video: Narrator: It's about repowering America. One of the fastest ways to cut our dependence on old dirty fuels that are killing our planet. Man: Future's over here. Wind, sun, a new energy grid. Man #2: New investments to create high-paying jobs. Narrator: Repower America. It's time to get real.
Al Gore: There is an old African proverb that says, "If you want to go quickly, go alone. If you want to go far, go together." We need to go far, quickly. Thank you very much. (Applause)