Ocean, Atmosphere, Ice, and Land - Bumps and Wiggles (8):

By: Dr. Ricky Rood , 4:27 PM GMT on June 20, 2010

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Ocean, Atmosphere, Ice, and Land - Bumps and Wiggles (8):

Introduction: This is the eighth (and last!) 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.

From the beginnings of the WU Climate Change Blog there have been entries on “natural variability.” A number of known modes of natural variability have been discussed. The most “famous” source of natural variability is El Nino, which is a warming of the sea surface temperature in the eastern Pacific. This warming changes the atmosphere, with the impact of these changes realized throughout most of the globe. El Nino and its related cold phase, La Nina, are part of an oscillating behavior characterized by several attributes. First, this is an example of the ocean and the atmosphere varying together - in a correlated way. Second, the ups and downs of the oscillation are not “regular.” That is, the time period is not the same from one oscillation to the next and the peak and the duration of the warm and cold phases varies a lot. Third, despite significant observations and the development of useful theories, we do not fully understand the mechanisms that cause the El Nino – La Nina cycle. Hence, our ability to represent El Nino in climate models could be substantially improved. For the purposes of this article these attributes can be summarized as - a not fully quantified example of the oceans and the atmosphere irregularly varying in sync with each other.

There are many such features in the Earth’s climate; that is, not fully quantified examples of the oceans and the atmosphere irregularly varying in sync with each other. Other important ones are the North Atlantic Oscillation and the Pacific Decadal Oscillation. (Summary of such variability) When compared with El Nino, these other oscillations are less well quantified, less regular, and the relation between the atmosphere and ocean is more difficult to describe. Another characteristic of these modes is that they slosh back and forth with characteristic times of several years. Hence, these modes contribute to the bumps and wiggles in the observations that are the subject of this series of blogs. Implicitly and intuitively, when people start to think about climate “prediction,” as opposed to “projection,” it is how to account for these sources of natural internal variability. This is and will be a hard problem. There are a few Big Points I would like to make.

Big Point 1: One of the spurious statements about climate change, climate models, and climate projections is that it is impossible to forecast the climate because we know that “weather” is “chaotic,” and cannot be predicted beyond, approximately, 2 weeks. (Chaos and Weather Prediction from National Geographic) This misconception is, perhaps, based on the idea that the climate is “average weather,” and therefore, we have to predict weather before we can predict climate. Several points – 1) We might not be able to predict weather on an event-by-event basis beyond a few days, but we are likely to be able to (and can pretty well) represent the “average” weather and the correct amount of variability. 2) The definition of climate as “average weather” is, in fact, an inadequate definition of climate based on our experience of focusing on the weather and weather prediction and knowing the most about the atmosphere. The climate is all about the ocean and ice sheets and land and how they interact with the atmosphere and impact people. 3) So the details of Lorenz’s famous and powerful theory about chaos and the atmospheric weather is not exactly relevant to the problem of climate prediction – or more concretely ocean prediction. 4) We know from our El Nino experiences that the atmosphere responds in a, more or less, predictable way to changes in the ocean. (El Nino responses La Nina responses) Therefore, if we can predict the ocean better, we can predict, more accurately, what will happen in the atmosphere and how climate change will impact man.

Big Point 2: Sometimes I hear in the criticism of climate change science that climate models and modelers and scientists do not account for El Nino, the North Atlantic Oscillation and all of these sources of natural variability. That models and scientists do not account for these processes is simply an untrue statement. Climate models that include the interaction of the ocean and the atmosphere do contain modes of variability that are “like” El Nino, the North Atlantic Oscillation, etc. They are like the phenomena that are observed on Earth, but they are not an event-by-event representation of the Earth. And while they are like these events, our ability to simulate these events is far from perfect. Remember, I said earlier, these sources of variability are not fully quantified examples of the oceans and the atmosphere irregularly varying in sync with each other. When we look for signals in the models of warming by greenhouse gases, that warming is deemed significant above natural variability in the models that is comparable in magnitude of what is observed. see wiggles on figure in this blog. When all of the models are added together and averaged, as is often done in the IPCC figures, all of this variability averages out; the projection appears smooth. For the purpose of this series of blogs, the real observations of temperature have bumps and wiggles that are not in the projections that are the source of the discrepancies I have been writing about.

Big Point 3: There are certainly other modes of atmosphere-ocean-ice interactions that we have yet to observe. Back in the 1990s while I was at NASA, Arthur Hou and Andrea Molod published a paper looking at the interaction between the tropics and high latitudes. This has been a subject of many papers over the years. There was a result that they found that has stuck with me; namely, they found a high sensitivity of the transport of heat to the Arctic to what was going on with the deep convection in the western Indian Ocean. (Hou and Molod) The “deep convection” is responsible for those incredible and sometimes dangerous storms near the equator that drive the Hadley Cell. (Hadley Cell 1, Hadley Cell 2) The two aspects of Hou and Molod’s study that struck me were first, the high sensitivity mentioned above, and second, how difficult it is to model the western Indian Ocean. In recent years I have been impressed by the body of work that is provided by P. D. Sardeshmukh and his colleagues, in this case, especially Joseph Barsugli. In a two studies focused on tropical sea surface temperature patterns, they find great sensitivity of global weather patterns to, yes, the Indian Ocean. (2002, 2006) (These go along with much more studied sensitivity to patterns in the Pacific.) I, rightly or wrongly, even extract from this work a potential clue about that warm period in the 1930s that gets a mention every now and then. The point, there may be, almost certainly are, ocean-atmosphere patterns that we have yet to observe adequately, much less model. We will need to do this better as we understand the bumps and wiggles in the temperature observations. In my opinion, the most important places to focus to improve our modeling ability are on the West Indian Ocean and the Northwest Atlantic Ocean. These studies need to be process-focused and to explicitly focus of how the ocean and atmosphere (and in the Northwest Atlantic the outflow glaciers of Greenland) couple together. It is a fact of history that we focus most on the atmosphere, next the ocean, and only recently ice sheets and glaciers. We leave the “coupling” to just happen. We must focus on the science of coupling to explain the bumps and wiggles and to develop a predictive capability.

Big Point 4: There are modes of variability that we have not even thought about. We are just beginning to introduce ice sheets into climate models. We already know that there are strong connections between glacial flow, glacial melt, and the presence of warm sea water (Learning Abount Ice, Fast Ice – Redux, Sea Ice in Hot Water). But we have really not had an observing system that would measure all of the components, and those modes of variability would be expected to have long time scales. We are just beginning to get real ice sheet models linked into climate models, and that gives us the opportunity to do some numerical experiments. But even weak-minded modelers, ultimately, rely on data.

Short Summary: What I have posed in this series of blogs on short term variability is that the community of climate scientists need to have a research focus on short-term variability, where short term is a “few” years. By a “few” I mean a couple of years to maybe a few decades. The reason for this focus is not only to develop the foundation for decadal climate prediction, but to also provide the intellectual depth to better use climate model projections, as well as to strengthen the credibility of using climate model projections in applications. It is of critical importance to increase the focus on coupling of components in climate models, with particular attention to the processes important for variability on time scales longer than “weather.”

r

Bumps and Wiggles (1): Predictions and Projections

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

Bumps and Wiggles (3): Simple Earth

Bumps and Wiggles (4): Volcanoes and Long Cycles

Bumps and Wiggles (5): Still Following the Heat

Bumps and Wiggles (6): Water, Water, Everywhere

Bumps and Wiggles (7): Blackness in the Air




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Quoting MichaelSTL:


Again, there is no "cooling cycle from the PDO", only that the deniers and cyclists want you to believe so. Unless you live on the West Coast, perhaps (it has been really cold there lately, just as a negative NAO makes it cold in the Southeast).

In fact, according to this, the so-called "cooling cycle of the PDO" makes the Gulf warmer (see right side, the left is the "warm phase" which has large areas of cold water, indeed, look at the scale - those areas of cold water are colder than those during the "cool phase", and vice-versa for the warm areas)!



Hmmm... That also suggests that the Southeast is also warm - coincidence (referring to current weather patterns)?


The oil could be adding to the effect.
Member Since: January 2, 2006 Posts: 127 Comments: 20401
It will be more like this trend (2006)

Why did you chose a straigh line?

Member Since: March 6, 2007 Posts: 0 Comments: 2212
Now you know why the GOM is so warm in that area!

Member Since: January 2, 2006 Posts: 127 Comments: 20401
BP should be held liable for hurricane damage in this region if it occurs due to the now warmer SSTs that they have caused!
Member Since: January 2, 2006 Posts: 127 Comments: 20401
The oil on top is a small fraction of what is underneath. Sadly, this deeper oil that is mixed throughout the water column from the dispersants will also be warmed to about the 1000 foot level as the sunlight can penetrate that deep thus making that water also jet fuel for hurricanes. As the water comes into contact with the sun heated oil it is heated by way of conduction and the oil prevents evaporation at the surface thus trapping more heat. We no longer have a open heat exchanger at the surface because the lid has been closed!
Member Since: January 2, 2006 Posts: 127 Comments: 20401
How much can that offset the cooling cycle of the PDO?
Member Since: January 2, 2006 Posts: 127 Comments: 20401
Notice how hot is now where the oil is near N.O., Ala. and Fla.? Two months ago it was the coolest spot in the GOM now it is the warmest.

Member Since: January 2, 2006 Posts: 127 Comments: 20401
As the BP oil spill continues to destroy marine life and ruin livelihoods along the Gulf Coast, conservationists, energy companies and diplomats are preparing for the next big showdown over drilling -- this time in the Arctic.

A Russian icebreaker set sail recently on a scientific voyage to chart its northern underwater boundary, part of its stated plan to claim large hunks of the Arctic for oil, gas and minerals.

Even though the United States is one of the five Arctic nations with a big interest up north (the others are Canada, Greenland/Denmark, Russia and Norway), U.S. diplomats may be left on the sidelines. That's because Congress still hasn't ratified the 28-year-old Law of the Sea Treaty that governs how nations develop resources beyond their boundaries.

"Right now we don't have a seat at the table," a senior State Department official told Discovery News. "There's a real question as to how we can move forward. And there is a risk that we would be left behind."Scientists from the U.S. Geological Survey estimated last year that the Arctic holds nearly a third of the planet's natural gas reserves and 13 percent of the remaining oil. As the polar ice cap disappears (one-quarter of the ice cover has melted since 1978), companies like Shell, Exxon and BP have found it easier to drill for petroleum riches. And that doesn't include vast stocks of Arctic fish, timber and even diamonds.

Link
Member Since: January 2, 2006 Posts: 127 Comments: 20401
I told you our warmer oceans are melting more ice. We need to cool them back off!

New Research Sheds Light on Antarctica's Melting Pine Island Glacier


Pine Island Glacier was once grounded on (sitting on top of) this underwater ridge, which slowed its flow into the sea. However, in recent decades it has thinned and disconnected from the ridge, allowing the glacier to move ice more rapidly from the land into the sea. This also permitted deep warm ocean water to flow over the ridge and into a widening cavity that now extends to an area of 1000 km under the ice shelf. The warm water, trapped under the ice, is causing the bottom of the ice shelf to melt, resulting in continuous thinning and acceleration of the glacier.

Link
Member Since: January 2, 2006 Posts: 127 Comments: 20401
Quoting JFLORIDA:
It looks worse.


Yep! It just may be the well from hell.
Member Since: January 2, 2006 Posts: 127 Comments: 20401
How many of you believe divine intervention can stop this?
Member Since: January 2, 2006 Posts: 127 Comments: 20401
With No Gulf Solution in Sight, Louisiana Turns to Prayer

On Wednesday, Louisiana state Sen. Robert Adley won unanimous approval of the resolution, which invites people of all faiths from within the state and around the U.S. to focus on divine intervention to find a solution to the crisis.

Link
Member Since: January 2, 2006 Posts: 127 Comments: 20401
Quoting skepticall2:


Are those SST's? Plus it looks to me like the Earth has been MUCH warmer than it is today.


No that's for global average temperature SSTs would follow that line pretty much as we know the ocean is pretty much in sync with the atmosphere. Correct? That is what Ricky implies!
Member Since: January 2, 2006 Posts: 127 Comments: 20401
As you can see we can only have have ice ages in cool glacial ages. You agree?
Member Since: January 2, 2006 Posts: 127 Comments: 20401
Can you see where 200,000 years ago is on this graph?

Member Since: January 2, 2006 Posts: 127 Comments: 20401
We can go back to when anatomically modern humans evolved from archaic Homo sapiens in the Middle Paleolithic period, about 200,000 years ago if you like.
Member Since: January 2, 2006 Posts: 127 Comments: 20401
Quoting skepticall2:


Ahh whats the ratio since 1979? What is the ratio for forever yea you don't know so what is the point of this again?


Forever is sure a long time isn't it? Surely longer than the Earth has been here right?
Member Since: January 2, 2006 Posts: 127 Comments: 20401
I wish the naysayers would do this simple investigation and compare monthly global record high SSTs since 1979 and compare them to the monthly global record low SSTs since 1979. What's the ratio?
Member Since: January 2, 2006 Posts: 127 Comments: 20401
Quoting MichaelSTL:


Nothing more than La Nina:



By the way, look at this - up, up and away!



The same site also shows SSTs - interesting that overall temperatures are still rising even as SSTs fall, suggesting that land temperatures are rapidly rising, that must explain why it has been so hot here lately - above average for the 30th consecutive day, last time was Dec 2006-Jan 2007 (2007 featured extreme land temperatures even as La Nina developed, setting a yearly record in fact).

Of course Spencer would say that, because he is one of those ice age alarmists... I knew that this would happen... as it did 3 years ago (and yet, we have been smashing temperature records left and right for a year now)


Shhhhh! Don't say that Spencer may get mad and make another chart showing otherwise! LOL!
Member Since: January 2, 2006 Posts: 127 Comments: 20401

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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.