Ok friends: We talked about climate change in class @ Purdue and I started talking to skeptics online & did a bunch more reading, and I wanted to share a couple of thoughts if you have a minute:

1. Nobody has explained this clearly. I realize that’s not news.

Climate change isn’t that complicated, and telling people over & over “this is REALLY important” without explaining it – well that doesn’t work. People want to know for themselves. In fact, if you want to skip this whole blog and go straight to the IPCC’s summary for policymakers, it’s right here.

2. The scientists at the Heartland Institute who are leading the denial movement are the same scientists who testified before Congress that smoking doesn’t cause cancer. The same people. The Heartland Institute is paying people to run climate change denial websites such as “Watts Up With That”. The Heartland Institute is paid by the oil industry and by the Koch brothers. It’s not like there’s chaos among scientists – it’s a campaign by these people.

3. Climate change has nothing to do with Liberals, Conservatives, Al Gore, or the Bible. It’s just science.

So – Here’s what I learned.

First, people have been pumping billions of tons of CO2 into the atmosphere. In the U.S. we’ve released 120 billion metric tons of carbon dioxide since 1990. And we are about 1/4 of the total emissions.

Carbon dioxide doesn’t simply go away; in 100 years, 80% of what we put out will still be there.

NASA just published images of the circulation of CO2 in our atmosphere:

Carbon dioxide is a natural part of the planet. It’s a trace gas in our atmosphere, it used to be measured at 180-280 parts per million. We need a small amount of carbon dioxide in our atmosphere in order to survive, because it traps heat.

But it doesn’t take much.

You can see how powerful carbon dioxide is on YouTube: Bill Nye has a clip where he puts thermometers on two jars, puts lids on them, shines lamps on them, and pumps CO2 in one. Both thermometers rise; the one with CO2 rises faster.

It’s been known since the 1850’s that carbon dioxide is a powerful warming gas. Human beings have been emitting CO2 since the Industrial Revolution, when we started burning fossil fuels.

In 1896, a Nobel prize-winning Swedish chemist named Svante Arrhenius hypothesized that pumping CO2 into the atmosphere would lead to global warming when CO2 levels doubled. He thought the process would take about 3,000 years and he believed it would be a good thing. Arrhenius said “We would then have some right to indulge in the pleasant belief that our descendants, albeit after many generations, might live under a milder sky and in less barren surroundings than is our lot at present.”

Where Arrhenius based his conclusions on tens of thousands of calculations (that he wrote out by hand!), researchers now have physical proof of the relationship between the Earth’s climate and atmospheric CO2 levels. How did they get this?

Researchers have been accumulating information about the Earth’s temperature history for decades.

Scientists started by examining layers of fossils, and they found periods when the Earth was lush full of growth (plants, animals, etc), and periods (“ice ages”) when it was cold and desolate. So that told them the climate varied.

Nowadays researchers have machines and equipment that let them pull up deep sediment samples that aren’t easily accessible. So now they can look further back in time at even more of the fossil record to get a sense of what the planet was like.

Heavy equipment also makes it possible to extract buried ice, which means paleoclimatologists (such as Lonnie Thompson at Ohio State University) can calculate ancient temperatures based on water isotopes in the ice cores.

Paleoclimatologists also study the atmosphere. In the 1980’s, scientists began extracting and analyzing pockets of ancient air trapped in Greenland’s ice, to find out what the atmosphere used to be like. In 1997, American and Russian researchers began measuring CO2 levels in microscopic air bubbles in the Vostok ice cores in eastern Antartica. They have collected data from samples going back 800,000 years.

On a graph their data show CO2 levels rising and falling in a fairly regular pattern. Scientists compared the CO2 data with graphs showing the Earth’s temperature during the same period of time. And found that they line up.

Here’s an overlay of the atmospheric CO2 and temperature graphs.

The temperature rises, then atmospheric CO2 levels rise, and then the temperature rises some more.

These graphs came from the EPA (US Environmental Protection Agency) and IPCC (International Panel on Climate Change) websites. As researchers have continued taking samples and improving their methods of analyzing data, they’ve found that the red and blue lines correlate even more closely than originally thought.

So, why does the Earth’s climate vary in a pattern like that? And why has the Earth had ice ages?

And wait, it’s pretty clear that the Earth’s CO2 levels were varying long before human beings ever put up factories and started burning fossil fuels, what’s going on with that?

The Earth’s warming/cooling cycles are called “Milankovic cycles” after the Serb mathematician who first described them in the 1930s.

Milutin Milankovic figured out that the Earth’s orbit isn’t always precisely the same. It varies ever so slightly from year to year, just a little bit of difference that means we get more sun at times. These cycles last about 100,000 years. He showed that other planets in our solar system do the same thing.

It was pretty mind-boggling at the time, to think that the Earth’s orbit varies slightly. Milankovic had explained the reason why the Earth alternates between ice ages and warm years, as identified in the fossil record.

And here’s an important point: Milankovic’s cycles led to a huge misunderstanding in 1972, when one particular Italian scientist, Cesare Emiliani, remarked at a conference “we may soon be confronted with… a runaway glaciation” and the media picked up on it. Next thing you know, there were news stories about an impending ice age. As the American Institute of Physics states, “He meant ‘soon’ as geologists reckoned time, in centuries or millennia.“

So, Milankovic cycles are not controversial; it’s accepted that the Earth’s orbits vary, and that’s why we have warm/cold cycles over periods of about 100,000 years.

In fact, I’m pretty sure Milankovic cycles are what Indiana Congressman Todd Rokita meant when he told me (via form email):

“I do not believe human-produced carbon emissions are the primary cause of global climate change. The science behind global warming indicates the earth warms and cools in cycles. This cyclical process existed long before the Industrial Revolution and more recent modernizations.”

The problem with Congressman Rokita’s argument is that Milankovic cycles don’t themselves cause CO2 levels to rise, leading to a warmer planet.

Just like summer doesn’t cause rain!

Rain comes from clouds.

CO2 comes from….

….the Earth! Particularly the ocean.

There’s CO2 in the atmosphere, but there’s a lot MORE CO2 stored in the oceans. Like five times more. And the oceans really like to store CO2 when the planet is cooler, because CO2 is a gas.

Those of us who like hot chocolate know that solids melt better in warm water, but gases are the opposite. Gases are stored in cool water.

So when the Earth reaches the part of the cycle where it gets a little more sun, the oceans warm a little bit. And as the oceans warm, CO2 is released. Which leads to more warming and more CO2 release.

That’s why an ever-so-slight change in orbit, increasing the sun we receive just a smidge, sets off other changes that add up to have a big effect on the Earth’s climate. Over time it has made the difference between warm periods (like the one we are in now) and ice ages.

You probably know that carbon dioxide is also stored in trees and plants as they grow (some trees are half carbon). It’s stored by marine animals who turn it into calcium carbonate (aka seashells). Carbon dioxide is also stored in the tundra and in glaciers. So carbon dioxide is released when the tundra melts, volcanoes erupt, and when trees and plants die and decay.

The Earth isn’t static, it’s always changing. The circulation of carbon from the atmosphere to the ocean is called the “Carbon Pump”.

So the carbon pump is why, prior to the Industrial Age, the Earth’s atmospheric CO2 level varied from about 180-280 ppm.

But take a look at the far right-hand side of the graph.

People started burning fossil fuels during the Industrial Revolution. We are putting a lot of it into the atmosphere and that’s where it stays. Atmospheric CO2 has risen dramatically and it’s is now 400 ppm. And global temperatures are rising.

Here is a detailed look at the past 1,000 years.

So if atmospheric CO2 controls the Earth’s temperature and it’s way up, why haven’t temperatures jumped up dramatically? And the amount of change on this graph is pretty small, less than two degrees really. Is that worth worrying about? When scientists say the temperature of the planet will rise by one degree, that seems pretty small.

Well, first, the Earth isn’t a pizza, it doesn’t bake evenly; on some parts of the planet the rise IS dramatic.

The poles are heating up first.

It’s a lot warmer in the Antarctic, an average of 2.8 degrees centigrade. Which may not sound like much, but is having a huge effect. Melting ice is flowing down to the sea, and the ice shelves are collapsing.

Some have proclaimed that sea ice is at “record highs” — well, think about what happens when you melt butter.

It spreads out.

That’s why researchers look at mass, not just surface ice.

In the Arctic, even the sea ice is shrinking.

How much water is stored in the Arctic and in Antarctica? What would happen if both of the polar caps melted someday?

Here’s an interactive graphic that shows what the U.S. would look like.

The ice covering Greenland is also melting.

Is this melting having any effects? Yes.

Sea levels are already rising, both in the U.S. and worldwide, because of melting in Greenland and Antarctica.

Melting glaciers don’t cause sea levels to rise (just like when the ice in your Pepsi melts, the level of liquid in your cup stays the same) – BUT, the ice in Greenland and Antarctica is over land.

And there’s another reason why our surface temperatures haven’t taken a huge jump.

Remember that the Earth is 2/3 water. The oceans are warming; they’re absorbing the heat we’re creating, acting as a buffer.

This warming has increased the melting of glaciers.

Which means there’s another problem.

The oceans are also absorbing half of the CO2 we produce, so they’re losing oxygen and becoming acidic. Parts of the oceans are dying. Coral reefs are in real trouble.

Even if you don’t live on the coast and you don’t like Polar bears, coral reefs, seals and lobsters, the health of the ocean is a critical issue.

Because the oceans are where we get oxygen.

Phytoplankton create 50-85% of the oxygen we breathe.

We are changing their environment by making it warmer and more acidic, and phytoplankton have declined over the past 100 years. Scientists haven’t yet figured out if phytoplankton will be able to survive the changes we are making.

That’s why scientists are urging people to act now.

Not because there’s a huge catastrophe anticipated this year.

But because small changes to the planet are leading to more changes.

Here’s another example:

As the Greenland ice sheet melts, the snow layers underneath the fresh snow aren’t as reflective.

So Greenland is absorbing more heat, and melting faster – the melting is magnifying the change. It’s called “dark snow” and you can read about it here, on Dr. Jason Box’s blog.

It’s not just in Greenland and the Antarctic. The loss of mountain snow is another climate change magnifier. Since snow is white, it typically reflects sunlight and acts as a temperature regulator.

We’re losing that, due to melting.

In Italy they’re putting blankets on this glacier, to try to make it more reflective.

Perhaps it’s hard to see everywhere. A snowy winter in North America makes global warming seem unlikely, right? Why do people blame tornadoes on global warming?

Well, keep in mind that heat isn’t just temperature. Heat is also energy.

When you heat up a pot of water, it doesn’t just get hot – it moves, because it’s full of energy.

“Heating up” the atmosphere is another way of saying “put a bunch of energy into the atmosphere”. That’s why bigger storms, more severe weather and more snow are predicted by climate change. That’s why 7 of the 10 most powerful hurricanes recorded happened in the last 15 years.

That’s also why people stopped saying “global warming”; “climate change” is more accurate.

There’s one more big concern.

Carbon dioxide isn’t the only greenhouse gas.

Methane is another warming gas that’s a natural part of our environment. Carbon dioxide is the one people talk about because we produce SO much of it and because it stays in the atmosphere for SO long. But methane is even stronger than carbon dioxide – 30x stronger. There are vast stores of methane in the permafrost (Siberia, Greenland, northern Canada, Alaska).

When the subject of global warming and methane was raised in the late 1980s, people made a lot of jokes about cow farts. Scientists didn’t fret overmuch because the methane was in the permafrost, where they figured it would stay. But what isn’t funny is the permafrost is already melting. And methane levels are on the rise.

That’s going to add more heat.

Some argue that human beings can’t possibly be powerful enough to control the Earth.

Well, they’re right: We don’t have control.

What we HAVE done, and are still doing, is push a lever that sets a chain of events into motion.

It’s not like we can change our minds and stop this train once it gets going – we can’t re-freeze the ice or de-acidify the ocean.

We can’t put the methane back into the permafrost.

Are the effects of climate change likely to be good?

Take another look at this graph, and notice that the -10 eras were ice ages. If -10 created an ice age, what would +10 do? Or +5?

When he was picturing a warmer and cozy Earth, it didn’t occur to Arrhenius how inter-connected the planet’s systems are. He didn’t know that the oceans would heat up and become acidic. He couldn’t see that warming gases would magnify their own effects and lead to even higher temperatures.

He also didn’t know there would be 7 billion people to feed.

“Almost everywhere you see the warming effects have a negative affect on wheat and there is a similar story for corn as well. These are not yet enormous effects but they show clearly that the trends are big enough to be important,” Lobell (of Stanford University) said.

Now, it is certainly fair to ask, has it really been proven that human beings are responsible for the current CO2 levels? Even with the billions of pounds of CO2 we’ve put in the atmosphere, what about those vast stores in the ocean that are just a natural part of the planet? Is there something else going on? What about other cycles?

Scientists looked into that. They used computer models to calculate what the Earth’s temperature would have been over the past 100 years without people’s CO2 emissions. Because yes, as we said, the ocean (and forest fires and volcanoes) put out CO2 also.

So scientists calculated what path temperature should have followed over the past 100 years, given the CO2 that comes from nature.

The actual temperatures didn’t follow that path – instead, temperatures rose in a pattern consistent with human influences.

Scientists did those calculations for every continent, and on every continent it was the same.

The Earth’s natural CO2 levels don’t account for the temperature increase. The only way the temperature increase can be explained is via the greenhouse gases put out by people.

And, there’s a specific way that our carbon dioxide can be identified. The CO2 in our atmosphere that’s from burning fossil fuels doesn’t have any Carbon-14 (C-14).

Carbon dioxide that’s “fresh”, that is part of the carbon pump cycle of life and death, has C-14. Carbon-14 is ever so slightly radioactive. It decays over thousands of years (that’s the isotope used to “carbon-date” fossils). So of course there isn’t any C-14 left in the fossil fuels we’re burning, because they’re millions of years old. Nor is there any C-14 in the CO2 that results, so samples that are taken today have carbon dioxide that can be specifically identified as coming from us.

Are the effects of climate change going to hit fully in the next fiscal year? Or the current election cycle?

Nope.

The effects are going to unfold over decades.

The problem is, we can’t stop them.

And the CO2 we put out today will still be here in 80 years.

The longer we wait to act, the worse it will be for our grandchildren.

So…………

…..I’m putting out all of this depressing information.

But I also learned a lot of good news in the class I took.

Ten years ago, a couple of Princeton scientists named Robert Socolow and Stephen Pacala figured out some authentic large-scale solutions.



They called their solutions “Climate Wedges” and they’re explained on this website. http://cmi.princeton.edu/wedges/

Here is what they say:

We Have the Technology

Each of the 15 strategies below has the potential to reduce global carbon emissions by at least 1 billion tons per year by 2060, or 1 wedge. A combination of strategies will be needed to build the eight wedges of the stabilization triangle. No one strategy will suffice to build the entire stabilization triangle. New strategies will be needed to address both fuel and electricity needs, and some wedge strategies compete with others to replace emissions from the same source. Still, there is a more than adequate portfolio of tools already available to build the stabilization triangle and control carbon emissions for the next 50 years.

Efficiency Double fuel efficiency of 2 billion cars from 30 to 60 mpg. Decrease the number of car miles traveled by half. Use best efficiency practices in all residential and commercial buildings. Produce current coal-based electricity with twice todays efficiency. Wind Increase wind electricity capacity by 10 times relative to today, for a total of 2 million large windmills. Fuel Switching Replace 1400 coal electric plants with natural gas-powered facilities. Solar Install 100 times the current capacity of solar electricity. Use 40,000 square kilometers of solar panels (or 4 million windmills) to produce hydrogen for fuel cell cars. Carbon Capture and Storage Capture AND store emissions from 800 coal electric plants. Produce hydrogen from coal at six times today’s rate AND store the captured CO 2 . Capture carbon from 180 coal-to-synfuels plants AND store the CO 2 . Biomass Fuels Increase ethanol production 12 times by creating biomass plantations with area equal to 1/6th of world cropland. Nuclear Add double the current global nuclear capacity to replace coal-based electricity. Natural Sinks Eliminate tropical deforestation. Adopt conservation tillage in all agricultural soils worldwide.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Perhaps it’s difficult to imagine we can fix the climate problem, but we’ve fixed others.

We cut out CFCs and now the ozone hole is slowly improving. Sulfur dioxide emissions are down and forest soils damaged by acid rain are slowly improving.

We can do this.

We must.