Simple Earth - Bumps and Wiggles (3):

By: Dr. Ricky Rood , 7:02 PM GMT on April 11, 2010

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Simple Earth - Bumps and Wiggles (3):

Introduction: This is the third in a series on understanding climate variability, global warming, and what we might do about it. The series focuses on the past 30 years and the next 30 years. This article is a bit of a restart; I feel I jumped the gun. Plus, of course, I think I have an important story that needs to unfold.

In the previous articles, see links below, I wrote that we are moving to a time when climate models will be used for more than providing guiding projections about how the Earth will respond to rapidly increasing greenhouse gases. The mantra in the field is to talk about decadal forecasts; however, the state of our observations and understanding of decadal variability are far from supporting a robust forecast of accurate spatial patterns of warming (and perhaps regional cooling) on times scales of decades. One focus that I pose is attention to the variability on, for example, the five year time scale for the last thirty years, now, and the next ten to thirty years. Bringing a focus to this variability will bring closer attention to the mechanisms and processes that cause variability, and it is a simple matter of common sense, that when scientists pay detailed attention to something, then we usually learn a lot more about it. It is sometime difficult to decide on the priorities of what to pay attention to next.

In the previous blog, I focused on the Sun and oceans. In the spirit of clarity, I think that I need to take a step back and draw a picture. There are a couple of things that I repeat tediously to my students and one of them is to draw a picture. So I drew the following picture, Simple Earth 1. It’s not great art, but pretty good given my skill with the pen.





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

In the figure I suggest land, oceans, people (animals), and plants. Up in the sky there is the Sun, even with a few suggestive spots on it. The hard part was to draw the greenhouse gases, that is, the gases that hold heat close to the surface of the Earth. The most abundant greenhouse gases are water and carbon dioxide. The greenhouse gases are represented by the pastel pinkish and blue layer between the Sun and surface. I drew it a little red on the bottom because greenhouse gases hold heat close to the surface, and they make it cooler higher in the atmosphere. Hence, I drew them a little blue on the top.

There is a fact that is implicit when we talk about climate, climate change, and the impact of global warming on the Earth. That fact is that our focus is first and foremost on the surface of the Earth, and that that focus is overwhelmingly influenced by an interest in what happens to people. When we focus on the surface of Earth and people, then we, implicitly, even more strongly pay attention to the land and the atmosphere that is closest to people. This high level of attention to what is really only part of our planet’s environment, embedded in a much larger environment, strongly influences how we measure, define and add up all of the mechanisms that cause variability in our environment.

Even in Simple Earth 1, there is a lot of complexity, both explicit and implicit. If we are going to understand how the temperature varies where the person is standing, then we might, reasonably, expect: 1) there to be changes in the energy coming from the Sun, 2) changes in the greenhouse gases that hold heat close to surface, 3) transfer of heat between the atmosphere, land, and ocean. Or we can just stand in the shade of the tree.

We developed a lot of experience and intuition over the centuries. It gets hot in the summer and cold in the winter, and that is strongly related to how bright the Sun is. It’s a little more complicated, but we also developed some intuition about the transfer of heat between the ocean and the atmosphere; the climate in California, Oregon, and Washington, is far different from the climate between Texas and North Dakota. These two groups of states span the same range of latitude, and intuitively, have the same “amount of Sun.” The difference is transfer of heat from the ocean.

As we try to quantify the variability, with the ultimate goal of predicting the variability, we come up against the vast complexity that is only hinted by this figure. That it is complex does not mean that we cannot do the problem; though it is a convenient excuse to maintain that we cannot – and always supplies a seed of uncertainty and doubt. The importance of our environment combined with our ability to alter our environment demands more and more ability to quantify and anticipate the changes that we might expect – whether they be “natural” or “human caused.”

In the previous two entries of this series (linked below) I jumped the gun a little bit. In the first article I wrote about how we had evolved past the standard of merely stating that the observed, specific variability of “the moment” was or was not consistent with our previous experience. The take away message, we have to measure and quantify the specific cause and effect of the bumps and wiggles that we observe. In the second article I wrote about “following the heat.” Therefore we have to first consider “the source” of the heat, the Sun, and how that changes. Then we have to put ourselves into that point of view of the person standing on the land in the lower atmosphere and ask – is it getting hot like the models have predicted? Well, the answer is yes, but he have to be smart enough to realize that some of the heat goes into the ocean, so we have to check whether or not the ocean is getting warmer at the same time that it is getting warmer where we live.

In this simple, first thought, the ocean is a sink of heat, but that is completely defined by that implicit point of view of the land-dwelling person. When I was a child, literally, very smart people said that “global warming” would not be a significant problem because the ocean is large and it “would just absorb the extra heat.” Well, it does absorb heat, but it takes a while, so when we get back to that human on the land, trying to grow that tree, it might get pretty hot before the ocean takes up that heat.

Of course, there is a detail, an important detail, what if the ocean gives back that heat? There is no reason to expect the ocean to just take up heat. The oceans are always giving back heat. Just go to California, or Britain, or the northwest Russian coast, or Trinidad.

With this restart and Simple Earth 1, it makes sense to start to march more carefully through the Bumps and Wiggles.


r

Bumps and Wiggles (1): Predictions and Projections

Bumps and Wiggles (2): Some Jobs for Models and Modelers (Sun and Ocean)


And here is

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Is anybody doing studies on the thermal effect of coating the ocean surface with plastic?
I'm not proposing we do it, we have already done it in the Pacific where all the floating junk and trash collect. Is anybody collecting water temperature data on the surface and at depth under the floating plastic masses?
Are they helping keep the ocean shaded and cool as a side benefit, or would cleaning them up help restore thermal balance?
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Hi,
Peter this side from Canada.The information that you had mention here on Climate. I would like to say to all for sharing their views on informative topic.

Peter

Living Room Furniture
Quoting skepticall2:
So let me get this straight. We started with surface stations who are in most part warm biased then we went to Satellites which are more accurate. Yet we base whether or not it is getting warmer on old warm biased surface station and comparing them to todays temperatures.


Actually, I think that the split between using "surface observations," and "satellite observations" is a fabrication of the political response to climate change science. It arises out of a singular focus on one data set or another, and finding the weaknesses in those data sets.

I think that if you look at the IPCC reports, you will see a reliance on several published data sets, which are used to evaluate correlative physics and inconsistencies.

I think that if you look at the history of the development of temperature retrievals from satellites, that you will see that they are strongly informed by conventional observations, and rarely stand alone as "most accurate," even by those who produce them.

In this case, the selective focus on individual data sets is not a form of scientific argument. It is based in a "belief" or "desire" to value an isolated source of information in order to make a point.

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№ 12
My chief point was that the IPCC's claim of accelerating warming was indeed a misleading interpretation.

I haven't seen any data claiming it hasn't warmed since 1900, or even since 1980 in fact, so I have no problem accepting that.

I believe the specific amount of warming and man's contribution are still up for debate as are long-term projections of temperature in the future.

"Old graphs"? I'm assuming these come from the IPCC's most recent report (2007, I think). Is that correct? Have they amended these? Do they no longer refer to warming as accelerating?
Member Since: February 19, 2010 Posts: 0 Comments: 580
Quoting AySz88:
One thing I'm wondering a bit about:

I know that increasing the amount of greenhouse gasses should make top of the stratosphere cooler than the lower part of the atmosphere - but does the stratosphere get cooler than before? I thought the temperature at the top of the atmosphere would have to stay nearly the same so that the radiated energy stays in balance with the (fairly) constant incoming energy? Or does more of the radiation to outer space end up happening nearer to the top of the troposphere or "top" of the greenhouse gasses? I'm not sure how the mechanism works there.


The presence of ozone in the stratosphere makes the simple greenhouse gas, upper atmospheric cooling complex. Ozone heats the stratosphere. As it decreases there is less heating, or really a shift downward of the heating. When it gets cooler, ozone chemistry slows down, ozone comes back.

So the place to look for the cleanest upper atmospheric cooling is uppermost troposphere, lowermost stratosphere, and we see that cooling in both satellite and balloon data.

It is perhaps more convincing to look at the trend in the top of the troposphere, which is rising. This essentially puts "colder temperatures closer to space," consistent with what you said.

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The New Math--IPCC version
Link

If they really wanted to show accelerating warming they should have taken it a step further and did a 12.5-year line... Oh, Wait.

I mean really...the IPCC claims to be objective and not politically motivated and then puts something like this in their report. Short time frames such as 25 years (or less) do not suggest much as far as long term warming. The time period 1915 to 1940 has a similar linear-fitted slope as the last 25 years. Does this mean warming hasn't accelerated since then? AGW proponents are always saying not to read to much into the relatively flat temperature trend since 1998--and I certainly agree this says little about long-term temperature variation. In my opinion this demonstrates the lack of objectivity by the IPCC. A truly objective report would show the raw data as it is and make your case with that data, instead of trying to make the data say more than it actually does.

Edited for grammar: Man, I never make grammar errors when writing. I'm beginning to think that keyboards really do make you stupid.


Member Since: February 19, 2010 Posts: 0 Comments: 580
One thing I'm wondering a bit about:

I know that increasing the amount of greenhouse gasses should make top of the stratosphere cooler than the lower part of the atmosphere - but does the stratosphere get cooler than before? I thought the temperature at the top of the atmosphere would have to stay nearly the same so that the radiated energy stays in balance with the (fairly) constant incoming energy? Or does more of the radiation to outer space end up happening nearer to the top of the troposphere or "top" of the greenhouse gasses? I'm not sure how the mechanism works there.
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Sadly, some scientist think this mass extinction event will be the worst one ever! Is it right to reverse the damage we have already done or is there enough time left to do so?
Member Since: January 2, 2006 Posts: 127 Comments: 20401
Yes, #2, cycles are natural. That does not mean that we don't know what causes the cycles - usually they are associated with vast changes of greenhouse gases. These changes occur as the gases are released from rocks and the ocean and strongly influenced by life. So today we are the life, and we release the greenhouse gases stored over many millions of years in a few hundred. Geologically this will appear as, yet another, cycle, warm temperatures, extinctions, one caused by a rapid release of carbon dioxide by burning. So this will be the one caused by mankind burning stuff. Seems simple enough.


As I see it, we have a stunning opportunity to do something about it, rather than being the hapless victim of "cycles."

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About RickyRood

I'm a professor at U Michigan and lead a course on climate change problem solving. These articles often come from and contribute to the course.