Cato Institutes claim on global warming disputed by most experts

[spiderman]

Cato Institutes claim on global warming disputed by most experts

 

A recent full-page newspaper ad from the libertarian Cato Institute takes issue with President Barack Obama's convictions about global warming.

 

The ad cites then-President-elect Obama's Nov. 19 statement: "Few challenges facing America and the world are more urgent than combating

climate change. The science is beyond dispute and the facts are clear."

 

"With all due respect, Mr. President, that is not true," the ad states in bold letters. Below that is a statement they say was signed off on by more than 100 named scientists.

 

"We, the undersigned scientists, maintain that the case for alarm regarding climate change is grossly overstated. Surface temperature changes over the past century have been episodic and modest and there has been no net global warming for over a decade now. After controlling for population growth and property values, there has been no increase in damages from severe weather-related events. The computer models forecasting rapid temperature change abjectly fail to

explain recent climate behavior. Mr. President, your characterization of the scientific facts regarding climate change and the degree of certainty informing the scientific debate is simply incorrect."

 

Global warming is a complicated subject, and we're not going to flesh it all out here. But we did want to address the underpinning of this ad, the claim that "there has been no net global warming for over a decade now."

 

First off, we should note that while there are some who disagree about the existence of global warming, the overwhelming consensus among scientists who study the climate is that it does, and that humans are worsening it.

 

The definitive statement on global warming comes from a 2007 study by the U.N. Intergovernmental Panel on Climate Change, a group of scientists from more than 130 nations. They concluded that the "warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice and rising global average sea level." The group also concluded that there is "very high confidence that the global average net effect of human activities since 1750 has been one of warming."

 

The problem with the assertion in the Cato statement is that it is impossible to make meaningful conclusions about climate trends based on looking at a 10-year window, said Richard Heim, a meteorologist at the NOAA National Climatic Data Center Climate Monitoring Branch.

 

People tend to think of global warming as a steady trend upward, Heim said, but that's not how it works. if you were to look at long-term trends, like a century, it looks more like steps. Temperatures will rise for a few years, then level off or even go down a little bit, then go back up. That's why you've got to look at temperatures over many decades, he said.

 

And if you look at the trends over the last 100 years, Heim said, "the overall linear trend shows clear, unequivocal, unmistakable warming over that period." Take a look for yourself at the NOAA graph of 100 years of global temperatures"

 

Now, over the last dozen years, he said, global temperatures have largely plateaued. That's consistent with the trends. Typically, he said, climates will go up, then plateau until they reach a tipping point, and then rise again.

 

"What you are seeing in the last eight or 10 years is kind of like one of those steps," Heim said. "The fact that it's not getting warmer doesn't mean we are not experiencing global warming. You can't talk about global warming over a 10 year period. The time scale is too short."

 

When you grab short time frames, say 10 years, it's easy to cherry-pick starting points that are particularly high or low to make your argument one way or the other. But even if you did select a 10-year frame — as cited by Cato — it would show a slight warming over time, Heim said. If you looked at just the last eight years, it would look flat. In fact, if you looked at the last four years, it would seem to be cooling.

 

"But this is crazy," Heim said. "You have to look at the big picture."

 

Gavin Schmidt, a NASA climate scientist who was a reviewer on the IPCC study, called the Cato argument that there has been no global warming over the last 10 years "fatuous and false."

 

"What if I said that there had been no global warming for an hour? You would rightly tell me that this was too short a period for it to be meaningful," Schmidt said. "The same is true for a 'decade'. But even so, it is false."

 

Schmidt directed us to a graph showing the 10-year climate trends using the four main temperature indices. The line bounces up and down like a lie detector graph, but the overall lines all trend upward.

 

"To be clear, the globe has warmed for the last decade," Schmidt said. "You can get different results if you pick out your start dates carefully, a practice known as cherry-picking since it is trying to use the data to say something other than what it generally shows, but you are much better off looking at the longest time scales you have (such as these from NASA )."

 

Cato cited a study on the internal variability of the climate system to support its claim. But the paper, from Kyle Swanson and Anastasios Tsonis, doesn't dispute the long-term trend of climate change, Schmidt said. He cited this conclusion from the paper: "If the role of internal variability in the climate system is as large as this analysis would seem to suggest, warming over the 21st century may well be larger than that predicted by the current generation of models, given the propensity of those models to underestimate climate internal variability."

 

Said Schmidt: "Quoting this paper to support a claim that global warming has stopped is like quoting Ronald McDonald in support of vegetarianism."

 

In conclusion, most scientists who study climate say that cherry-picking a 10-year window is inappropriate. But in this case, cherry picking exactly 10 years (Cato said a decade) still doesn't support their claim. We rate this claim False.

[Balta1701]

I'm not sure we need a new thread for this.

[Jenksismyhero]

The problem with the assertion in the Cato statement is that it is impossible to make meaningful conclusions about climate trends based on looking at a 10-year window, said Richard Heim, a meteorologist at the NOAA National Climatic Data Center Climate Monitoring Branch.

 

People tend to think of global warming as a steady trend upward, Heim said, but that's not how it works. if you were to look at long-term trends, like a century, it looks more like steps. Temperatures will rise for a few years, then level off or even go down a little bit, then go back up. That's why you've got to look at temperatures over many decades, he said.

 

And if you look at the trends over the last 100 years, Heim said, "the overall linear trend shows clear, unequivocal, unmistakable warming over that period." Take a look for yourself at the NOAA graph of 100 years of global temperatures"

 

Now, over the last dozen years, he said, global temperatures have largely plateaued. That's consistent with the trends. Typically, he said, climates will go up, then plateau until they reach a tipping point, and then rise again.

 

 

This is a completely unpersuasive argument. The exact same can be said about him. He's using a century or two of data to prove a warming trend. What happens when you look at the last ten thousand? Couldn't we just be in another warming "step?"

[Balta1701]

This is a completely unpersuasive argument. The exact same can be said about him. He's using a century or two of data to prove a warming trend. What happens when you look at the last ten thousand? Couldn't we just be in another warming "step?"

Then there needs to be an explanation as to why the planet's climate has decided to move in steps.

[BigSqwert]

Spiderman, you should cite your source.

[lostfan]

Spiderman, you should cite your source.

^^

Thanks BigSqwert, I didn't notice.

 

This isn't a Soxtalk rules thing, it's a legal and ethics thing. Same basic reason you have to cite sources in papers for school.

Edited June 10, 2009 by lostfan

[BearSox]

Then there needs to be an explanation as to why the planet's climate has decided to move in steps.

 

Question... hasn't the planet been going through climate changes it's whole existence? If so, why should we worry so much about this one? Why do we have to change everything we do if this could be a natural happening?

[kapkomet]

Question... hasn't the planet been going through climate changes it's whole existence? If so, why should we worry so much about this one? Why do we have to change everything we do if this could be a natural happening?

Man is an evil motherf***er. He has to be stopped, because He's too greedy.

 

 

[BearSox]

Man is an evil motherf***er. He has to be stopped, because He's too greedy.

 

Not all men... America altogether. If it wasn't for this country, the world would be a much better place.

[NorthSideSox72]

Question... hasn't the planet been going through climate changes it's whole existence? If so, why should we worry so much about this one? Why do we have to change everything we do if this could be a natural happening?

1. Yes of course the planet has seen a lot of climate changes over time. We've had ice ages, for example, and all sorts of other changes.

 

2. As to why people worry about it... let's just take the whole anthropogenic part out of it for a moment... regardless of cause, if for example the temperature on the planet rises (on net average) by a couple degrees, the level of the oceans will rise by numerous feet. This means entire cities, like say New York, will be flooded, unless you undertake massive engineering projects to prevent that. It also can mean all sorts of other damaging things from more intense storms, melting glaciers depleting water tables, less green matter on land to eat up pollution making that worse... there is a whole cascade of problems it would cause, REGARDLESS of whether or not humans effect it. So its a reality that needs to be dealt with.

 

3. The science on this is just so overwhelmingly in one direction that there is no logical argument to be made on the other side. The climate changes we are seeing are caused, in some part, by us. And just plain common sense should tell you that anyway - do you really think the 6 billion people on this planet and all their industry doesn't effect their environment? Now, there of course is plenty of debate as to how much of this change is anthropogenic. Could be only a little of it, might be a lot, that is very much up for debate.

 

You can choose to ignore it, but its really just like choosing to ignore the train coming at you. You do so at your own peril. I prefer that we make some adjustments (and there is LOTS of debate to be had as to what those should be) and, you know, keep the planet liveable for our kids.

 

 

[lostfan]

You know, I was wondering something and I figured Balta would be able to answer this - doesn't water expand when it freezes? Wouldn't that mean if it melted, the overall volume decreased? How does that work?

[NorthSideSox72]

You know, I was wondering something and I figured Balta would be able to answer this - doesn't water expand when it freezes? Wouldn't that mean if it melted, the overall volume decreased? How does that work?

I'm not Balta, but I can at least partially answer this one.

 

Glaciers and ice caps are currently above water. They melt, they add to the overall volume of ocean water. That also changes the salinity as well, but I am not sure of what impact that has.

 

[Balta1701]

I'm not Balta, but I can at least partially answer this one.

 

Glaciers and ice caps are currently above water. They melt, they add to the overall volume of ocean water. That also changes the salinity as well, but I am not sure of what impact that has.

You're correct. Melting the ice sheet at the north pole, melting the portions of glaciers/ice streams that are already floating has virtually no effect on the volume of the oceans. The issue is the amount of ice sitting on top of Antarctica, Greenland, and all the other spots.

 

Lost, you are correct that Fresh water ice is less dense than fresh water. In Fresh water, the maximum density is reached at about 4 degrees C. In other words, if I put a layer of fresh water at 1 degree C on top of a layer of water at 4 degrees C, they will not mix unless I stir them; the colder water will float on the warmer water.

 

You'll note though that I said Fresh water. When you add salt, you change the structural character of the water and the density maximum moves. In water that's as salty as the ocean; ice is still less dense than the ocean water and will float, but that's in no small part because salt doesn't go in to ice. Salt water that is at 0 degrees C though will still be more dense than water at 4 degrees C: the density inversion point moves out of the field where water is stable when you add a little bit of ice.

 

In terms of eustatic sea level rise that doesn't really matter but it's kinda cool. Fresh water at 0 degrees C will float on warmer water, salt water at 0 degrees C will sink.

 

The other area where your question is relevant is that thermal expansion due to warming of the earth is actually playing a role in the sea level rise we're seeing right now. The earth is on average getting warmer, the oceans are warming, and they're expanding and consuming Pacific Islands.

[Balta1701]

Question... hasn't the planet been going through climate changes it's whole existence? If so, why should we worry so much about this one? Why do we have to change everything we do if this could be a natural happening?

To put NSS's answer another way...basically the issue is not that the Earth can't take changing climate. It's that we can't. Our society is extremely adapted to a particular set of climactic conditions, and there's good reason to think that we've managed to do some primitive form of geoengineering in the past 10k years to keep it that way.

 

It's not just cities being flooded. It's agriculture. It's water supplies. It's extreme weather in general. The Sahel drought in Africa a couple decades ago is a great example. People there were getting by producing a certain amount of food based on the amount of rain that came. But as the planet started warming, that area was one of the first to dry out more, and suddenly we were looking at tens of millions of people starving over 1/3 of Africa. You warm the climate, and all the crops that are currently grown in the U.S. (Corn, wheat) can no longer be grown there because the summers are too warm and dry. The corn growing zone shifts northwards to Canada, and the economy of the central U.S. is wrecked. You warm the climate, and areas that survive based on water from snowfall or glaciers (i.e. California, or places all around the world in mountain ranges) suddenly have less water than their people need, agriculture dries up, and famine sets in.

 

And on top of that, extreme weather in general just isn't something humans do well with. Things change, like 500 year floodplains suddenly being flooded once every 10 years (Hi Iowa). Or you get more common heat waves that kill people. Or you get more tornado-producing storms. Or you get more/stronger tropical cyclones.