Dr. Ricky Rood's Climate Change Blog

Point of View

Posted by: Dr. Ricky Rood, 06:03 GMT le 23 août 2012

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Point of View: Models, Water, and Temperature (6)

This is a series of blogs on models, water, and temperature (see Intro). I am starting with models. In this series, I am trying to develop a way to build a foundation for nonscientists to feel comfortable about models and their use in scientific investigation. I expect to get some feedback on how to do this better from the comments. In order to keep a solid climate theme, I am going to have two sections to the entries. One section will be on models, and the other will be on a research result, new or old, that I think is of particular interest.

Doing Science with Models 1.3: In the previous entry of this series I used the example of balancing a monthly checking account to make the point that studying the Earth’s climate is very much like balancing a budget. Rather than money, we calculate a budget of energy.

Energy is one of the attributes used by scientists to describe the physical world, and it is a basic law of classical physics that energy is conserved. There are the laws of conservation of energy, conservation of mass, and conservation of momentum. Momentum describes how an object is moving: its mass, its speed, and its direction.

I introduced the concept of making a mathematical representation of the real world with this equation for money

Today’s Money = Yesterday’s Money + Money I Get – Money I Spend

and I came to point where I said we have a similar equation for energy

Earth’s Energy Today = Earth’s Energy Yesterday + Energy Gained – Energy Lost

These equations are the most basic models for the process that they describe. In fact, these equations could be said to be the perfect model for your personal budget of money or the Earth’s budget of energy. In the jargon of the scientist who builds models, this perfect model is often called the “analytic” model because it can be solved exactly, or analytically, by arithmetic.

The next idea I want to introduce is point of view. In the first instance, above, the equation represents a personal budget. In the second instance, the equation represents the energy budget of the whole Earth. Recall in the previous entry when I set up the problem of looking at the Earth’s energy, I said to imagine a person not on Earth, but who is observing the Earth. The observer, perhaps on Mars, sees the Earth as a small dot with energy coming in from the Sun, which the Earth then emits back to space from the Earth. If the Earth is in an energy balance, then the amount on energy coming back to space equals that coming in from the Sun.

That’s interesting to think about for a minute. Let’s assume that the Sun is constant. Then if the Earth is in an energy balance, the energy coming back to space is the same no matter the amount of carbon dioxide in the atmosphere. So to the person on Mars, the Earth would look the same. But the conditions on Earth might be quite different if the atmosphere had 600 rather than 300 molecules of carbon dioxide per every million molecules of air. This is because the point of view that we are interested in is from the surface of the Earth.

In 2010 I had a series of blogs called Bumps and Wiggles (here, go back and give it some “likes”). In the third of that series, I introduced Simple Earth. Here is that figure, which is described more completely in the original blog.

Figure 1: Simple Earth 1: Some basic ingredients of the Earth’s climate.

The problem of climate and climate change is important because of our point of view. If we are to continue to build thriving economies in our societies, we need a stable climate. In this case, stable really means that we know what to expect. Therefore, the climate of the Earth that might be of interest to that person sitting on Mars is not especially relevant to the person sitting on the surface of the Earth. Therefore, we need to think of models that are from the point of view of the person on the surface of the Earth. Again, energy and the law of conservation of energy come to the forefront.

In the figure, if the stick man looks around there is energy everywhere. It comes as heat from the Sun. It comes as wind from the air. It comes as waves from the sea. It comes as food from the land. So the accounting problem becomes more complex. We need the budget of energy for the atmosphere, the oceans, the land, and the glaciers and ice sheets. This energy needs to be balanced with what comes in from the Sun and what goes back to space. It is the same simple-to-conceive classical physics, but since we are in the middle of it all, the problem becomes complex. Still though, it is only a matter of balancing the books.

Interesting Research: Warming and Cooling in Ice Sheets - I’m usually not the blogger reporting on the most recent papers and breaking research, but this week I am different. The paper is Recent Antarctic Peninsula warming relative to Holocene climate and ice-shelf history, which was published online on August 22, 2012 in Nature. Robert Mulvaney is the senior author. The press take on this paper is that ice-core data show that over the previous, approximately, 12,000 years (the Holocene), there have been a number of times when there has been warming on James Ross Island, an island off the Antarctic Peninsula. These periods of warming have been comparable to the warming observed in the last 50 years, and hence, there are examples of warming that are not caused by the recent increases in carbon dioxide. There are scientific and political consequences of this paper. I will try to think like a scientist.

What does this paper say about generalized warming of the planet due to green house gases? First, we have to look at the locality of the data. It is from a single small island, in a part of the world that is known to have substantial fluctuations of temperature. We then need to look at how this knowledge fits in with the body of evidence as a whole. For example, Mulvaney and coauthors found a prominent warming period about 600 years ago. Was this warming at James Ross Island accompanied by warming of the same global extent as the currently observed warming? Are there other existing data that suggest natural internal variability during these previous times of warming? Is there something different in the past 50 years that distinguishes the current warming from the previous times of warming? The list goes on. So this result needs to be placed in context of all of the data and knowledge, and the coherence of this new information with the existing information needs to be evaluated.

This paper highlights the difficulty of extracting the contribution of warming due to carbon dioxide increase for any particular event. Ages ago, I had a blog on the breakup of the Larsen Ice Shelf. This new result makes the easy attribution of that ice-shelf collapse to human-caused warming difficult. As above, that attribution problem requires looking at the ice- shelf collapse in concert with other information. Was the event isolated? Is there evidence of other causes of variability? Is there something now that is different from the past? One attribution question that I can see – can the extra warming from carbon dioxide push the melting of the ice shelf over a tipping point?

Finally, I will bring us back to models, as models are ubiquitous in climate science and science in general. Within this paper, a glaciological model is used to determine the age scale. This model represents the flow of ice in the glacier, and that flow is assumed to remain constant over the time of the study. Another place that a model is used is determining the temperature based on the observations of isotopes of oxygen. This requires a melding of theory and application. Therefore, when you say, “but the observations show …” remember the role of models in making those observations.

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Categories: Climate Change Climate Models Climate Change Attribution

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151. Birthmark 14:02 GMT le 31 août 2012
Quoting ClimateInfidel: I do not care about the evidence. Those who hold power have too much to gain by convincing us that this temperature increase, unlike those that have come before, is our fault.I fear a global government with the power to control people to the extent it would take to control "greenhouse" gases much more than I fear global warming. Social engineering on that level would lead to a global dictatorship and unprecedented oppression. Environmentalism is just recycled communism! Thanks for pointing that out. Tin foil hats are down the hall, third door on the right. Member Since: 30 octobre 2005 Posts: 0 Comments: 1428

152. pintada 15:00 GMT le 31 août 2012
Quoting Xulonn: Oh damn - "The Onion" of climate change blogs - and I got suckered. Even when you face a great crisis, you've got to lighten up occasionally - or you'll go crazy or become seriously depressed. This segues wonderfully into something that i've been obsessing about as i work in the garden or on a project. The fact is that we can learn everything we need to know from popular media and - of course - the blogsphere. Knowledge Brings Fear - moto of Mars University Leela - "Lets go skiing." Fry - "Skiing? So, global warming didn't happen after all." Leela - "Oh, it happened ... Thank God nuclear winter cancelled it out." And we must never ignore the life lessons offered by my heros Bill and Ted: While on their bogus journey, they were cast into the pit. On the way down, they of course screamed like little girls. Then, they looked at each other, took a deep breath and screamed some more. Finally, they could do nothing but make small talk. Party on, Dude! But ultimately, we must all admit our failings and come to the true faith. I found salvation at : Landover Babtist "If you don't find God at Landover Babtist find God elsewhere." ( CAUTION: These true believers pull no punches) Member Since: 15 juillet 2012 Posts: 0 Comments: 128

153. Neapolitan 15:00 GMT le 31 août 2012
Quoting ClimateInfidel: I do not care about the evidence. Thank you for so honestly and concisely summarizing the denialist point of view. Such candor is quite sad, but nevertheless refreshing. Member Since: 8 novembre 2009 Posts: 4 Comments: 11154

154. pintada 16:47 GMT le 31 août 2012
Quoting ClimateInfidel: I do not care about the evidence. Those who hold power have too much to gain by convincing us that this temperature increase, unlike those that have come before, is our fault.I fear a global government with the power to control people to the extent it would take to control "greenhouse" gases much more than I fear global warming. Social engineering on that level would lead to a global dictatorship and unprecedented oppression. Environmentalism is just recycled communism! Too true brother, you have hit the nail on the head! These Eco Fascists (or as you would have it EcoCommies) trot out their "proof" and their "evidence" at every turn, but I know (and you've noticed it too) that all that "proof" is provided by scientists. Yes, incredibly, they believe the scientific "evidence" when you and I know the only real knowledge is provided by a good protestant pastor! Then they start with the guilt. The polar bear is going extinct - Boo Hoo. Red blooded americans like you and I don't care about a few bears. Anyhow, I hear that they are dangerous when not in a zoo anyway. If a few billion NON-americans die what do you and i care, right ClimateInfidel? You bet you're right. Heck, most of them aren't even pure blooded anyhow. According to the EcoFreaks, no new conventional oil has been found in the US since 1972, and the fracing now being done might pollute a little groundwater. The EcoCommies don't realize that - Drill, Baby Drill!! - is the answer. God will keep that oil flowing for us and make us enjoy the taste of fracing fluid to boot! Its just like our brothers at the GOP convention are saying. Pray, cut taxes for the wealthy (of course we both know they mean white when they say wealthy, Praise God), let corporations do anything and everything they want, and push the poor in front of a bus in lieu of medical care. We have the Supreme Court, if we can just get the Presidency and Congress too we can make some real progress!! Before you know it we'll be stoning gays and burning witches just like the bible demands! As white christian Americans, we have the God given right to our Hummers and our modest 3000 sq ft houses! Its so refreshing to see a post from a true American!! Keep it up, ClimateInfidel! America needs you!! Member Since: 15 juillet 2012 Posts: 0 Comments: 128

155. Some1Has2BtheRookie 17:24 GMT le 31 août 2012
Deleted Member Since: 24 août 2010 Posts: 0 Comments: 4102

156. SteveDa1 17:30 GMT le 31 août 2012
Please 'pintada' and 'climateinfidel', take your nonsense elsewhere. This is a science blog, not some conspiracy-theorists board meeting. Member Since: 17 octobre 2006 Posts: 59 Comments: 1057

157. Daisyworld 18:07 GMT le 31 août 2012
Quoting SteveDa1: Please 'pintada' and 'climateinfidel', take your nonsense elsewhere. This is a science blog, not some conspiracy-theorists board meeting. I think WU needs to implement a "sarcasm meter" so authors can better convey the intended sarcasm of their comments... Member Since: 11 janvier 2012 Posts: 4 Comments: 315

158. SteveDa1 19:41 GMT le 31 août 2012
Oh, in that case... Congrats pintada, you really had me! :) Member Since: 17 octobre 2006 Posts: 59 Comments: 1057

159. pintada 21:23 GMT le 31 août 2012
Quoting SteveDa1: Oh, in that case... Congrats pintada, you really had me! :) LOL No problem. Comedy is always done without a net. Sometimes the material just doesn't work. :-) Blame it on Xulonn, he's the one that got me started. :-) Comments 140 and 143 LOL Member Since: 15 juillet 2012 Posts: 0 Comments: 128

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