Iconic Figure # 1: CO2 trends
Iconic Figure # 1: "Keeling" CO2
In my class I have a set of figures that I call the "iconic figures" of climate change. There are only a handful of them, and they are the figures that I think all of my students should be aware of and understand. One of the exercises that I suggest for my students is to write a figure caption for each of the figures. (Perhaps an extended figure caption.)
Here is the first figure, which has been mentioned by a number of people commenting on recent blogs. This is often known as the "Keeling curve," named for the C. David Keeling who started to take CO2 observations at Mauna Loa in 1958. These data are now taken and maintained by NOAA's Earth Systems Research Laboratory, Global Monitoring Division. This web site is excellent, provides references, as well as access to the observations. Here is a recent update of the Keeling Curve. 
Figure 1: Carbon Dioxide at Mauna Loa Observatory.
There are two obvious things in this record. The first is that there is a steady upward trend of CO2. The second is that there is an annual oscillation of CO2. What is not so obvious on this scale is that the amplitude of the annual cycle is increasing. Here is a link to the NOAA site which has much more information on this figure, as well as global averages and numbers of how much the CO2 increases each year.
The steady upward trend is mostly attributed to the release of CO2 by fossil fuel burning. There has been significant effort to account for all of the sources (and sinks) of carbon dioxide, and the increase both correlates with the increased burning of fossil fuels, and it is generally consistent with amounts that are estimated based on fuel consumption.
Some have criticized the use of these particular observations because they are at Mauna Loa, which is a volcano. While this is true, the observatory at Mauna Loa was chosen because, to a very good approximation, it sees clean maritime air. This is constantly checked. One way it is checked is to calculate trajectories to see where the air being sampled comes from. Here is a link to recent trajectory calculations. If there is active volcanism, then is accounted for in the data quality control. It is found, more and more, that the air at Mauna Loa sees emissions and pollution from Asia. This is much more likely than seeing local volcanism.
There has been some significant effort to calculate the CO2 emissions from volcanoes. In the recent time, last 100 years, this amount is estimated to be more than 100 times smaller than that from fossil fuels. Here is the link to the USGS web site on volcanoes. With satellites and other observing systems, there are not any volcanoes in some hidden part of the world that are unknowingly spewing large amounts of CO2 or SO2 or aerosols into the atmosphere. Really.
Back to the Keeling Curve: The annual cycle in the CO2 is caused by the "breathing" of the terrestrial biosphere; that is, plants. Plants use CO2, and when the northern hemisphere blooms in spring and summer, the plants take up CO2. In fall and winter, there is release of biospheric CO2.
Not completely obvious in this figure, but more obvious in stations from high northern latitudes, the amplitude of the annual cycle is increasing. This increase is directly correlated with the "greening" of both North America and Siberia. Because of the warming at higher latitudes, there is greater growth of trees (easily measured by satellites). This greater growth takes up more CO2. On one hand, this increased "breathing" is consistent with the predictions of global warming; hence, it is part of the finger print that contributes to the validation of the theory. On the other hand, some have maintained that the increased biological activity would "take up the extra CO2." There seems to be no evidence to support this assertion, and the observations suggest that increased biological activity cannot keep up - at least on the time scales we have observed.
While it is possible to substantiate that the Mauna Loa station is not, in general, contaminated by local pollution, this substantiation is not generally accepted as adequate. It needs to be validated. One way to do this is to take observations at many other sites. Here is a list of other sites in the carbon observing network. If you were to study the observations from these sites, you would see a consistent signal. CO2 is increasing; there is biological breathing, and the amplitude of the breathing is increasing. However, the amount of CO2 does vary, especially as a function of latitude. This variation reflects a number of items. First, it reflects the enhanced emissions of the industrialized nations. Second, since these stations are located primarily in the northern hemisphere, there is more CO2 in the north than the south. This difference between the hemispheres can be used to estimate how long it takes the two hemispheres to mix.
I will leave it there. Wait for comments, and ask - what are the differences between the northern and southern hemispheres in terms of CO2?
r
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below.
The Arctic Oscillation Index goes strongly negative
28 12 2009
Link
In the last month, the Arctic Oscillation Index (AO) has gone strongly negative. You can see that it headed to its negative peak right about the time the Copenhagen Climate Conference started, so it is no wonder that they ironically experienced cold and snow there. It is also a setup for the record snow and cold Canada and the USA has seen recently.
see link for graph
Source: NOAA Climate Predication Center Daily AO Index
With this change happening, the setup for an increased Arctic Sea Ice Maximum is enhanced this year, likely to happen sometime around March 1st, 2010.
NSIDC has an interesting writeup and graphic on the AO:
Image from NSIDC: artwork by J. Wallace, University of Washington
From NSIDC:
The Arctic Oscillation refers to opposing atmospheric pressure patterns in northern middle and high latitudes.
The oscillation exhibits a %u201Cnegative phase%u201D with relatively high pressure over the polar region and low pressure at midlatitudes (about 45 degrees North), and a %u201Cpositive phase%u201D in which the pattern is reversed. In the positive phase, higher pressure at midlatitudes drives ocean storms farther north, and changes in the circulation pattern bring wetter weather to Alaska, Scotland and Scandinavia, as well as drier conditions to the western United States and the Mediterranean. In the positive phase, frigid winter air does not extend as far into the middle of North America as it would during the negative phase of the oscillation. This keeps much of the United States east of the Rocky Mountains warmer than normal, but leaves Greenland and Newfoundland colder than usual. Weather patterns in the negative phase are in general %u201Copposite%u201D to those of the positive phase, as illustrated below.
Over most of the past century, the Arctic Oscillation alternated between its positive and negative phases. Starting in the 1970s, however, the oscillation has tended to stay in the positive phase, causing lower than normal arctic air pressure and higher than normal temperatures in much of the United States and northern Eurasia.
As we see in this graph below, we%u2019ve seen more red (positive) than blue (negative) phases of the AO in the last 30%u201340 years. Whether this is short period negative excursion or the start of a longer trend is unknown.
see link for graph - The standardized 3-month running mean value of the AO index. The departures are standardized using the 1950-2000 base period statistics.
Source: NOAA Climate Prediction Center
There are other indicators recently of a flip in patterns, notable is the Pacific Decadal Oscillation which changed last year, but we also see the North Atlantic Oscillation in a negative phase as well. Whether it will remain negative or not we%u2019ll soon know, but note that it has been negative the majority of time since August 31st.
see link for graph
Source: NOAA Climate Prediction Center
Since 2000, it has seen a fair amount of negative time also:
see link for graph
Source: NOAA Climate Prediction Center
The climate change seems to be changing now.
h/t to Werner Weber
Link
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Philip T. Downman (23:27:11) :
The big question is: What is the motor of those changes?
Meteorologists seldom look higher than the stratosphere. Some of them look into the sea too. Their prognosis seem to be falsified already.
As someone pointed out, this corresponds quite well with Piers Corbyn%u2019s forecasts. Is that pure chance or has the guy got a real track? Not yet falsified as far as I can see.
And how about Svensmark? Sparse sunspots for the last two years should be followed by cooling, according to him. Does his theory still hold?
%u201D DirkH (19:51:44) :
BTW Mojib Latif , german Climatologist in Kiel, has predicted something like this with a computer model that incorporates the thermohaline convection. He is a convinced warmist and warns that this will give us only a break before rapid warming happens (no surprise there).
%u201D
Though that seems like an %u201Cad hoc hypothesis%u201D aimed to save the AGW theory, it will soon be honestly tested against reality.
pwl (20:50:50) :
What would be really interesting is seeing a 3d volumetric time series in fine resolution of the entire atmosphere and ocean currents. I wonder if this is even possible given the current set of data collected from the various satellites and other data collection equipment in play today. This fine resolution volumetric visualization mapped onto Google Earth in real time or near real time would enable people, just about anyone, to see a detailed map aka representation of what is going on with the planet at any given moment in time. Correlate the upper atmosphere and solar winds and influence of the moon as Piers Corbyn alleges would also be fascinating.
It sure looks like Piers Corbyn called it right using a forecasting model based upon the Arctic Oscillation Index and comprehension of the diagram you show above. Cold blowing across Europe and Canada/USA in the NO graphic as Piers forecast. Fascinating.
(for graphs)
Link
E.M.Smith (01:19:44) :Link
QUESTION
Peter of Sydney (19:53:38) : How come all this cooling around much of the world over the recent few months is not reflected in the official surface temperature readings as reported by NASA? I smell a rat.
ANSWER
Well you might%u2026 NOAA via NCDC, creates the GHCN data set that is the %u2018base%u2019 data (have trouble calling it %u2018raw%u2019 since it isn%u2019t%u2026) that goes into CIStemp (and if the leaked emails are to be believed substantially matches CRU, and so HadCRUT, and the NCDC adjusted, and even the Japanese series). That data series has had cold thermometers strongly removed in recent years (since 1989 or so) but they are left in the baseline. IMHO, this biases the input data via thermometer change so much that it swamps the ability of the %u201Canomaly process%u201D to recover a valid anomaly.
In other words, the input temperatures are cooked. A lot. 90% of peak thermometer count has been deleted. California, for example, has 4 surviving thermometers. One at SFO Airport near the San Franciso Bay (final approach is over water%u2026 water moderates cold%u2026) and three are %u201Cnear the beach%u201D in Southern California. Places like San Diego, LA, Santa Maria. Nice warm SoCal beach weather. (San Diego is darned near paradise. 70 something F almost year round -/ a little. You can grow bananas and get fruit %u2013 that is, the real tropical bananas, not those fruitless cool tolerant things%u2026)
So how can you get %u201Ccold%u201D in California when you leave out the Cascades, the glaciers of Mount Shasta, the Ski Resorts of the Sierra Nevada%u2026 Heck, the whole northern 1/3 of the state. Similar things are done to the rest of the world. For more details, tour the world thermometer deletions here:
http://chiefio.wordpress.com/2009/11/03/ghcn-the-global-analysis/
Since the climate of earth has been dynamic for it's entire history, why has mankind suddenly developed the notion that it is powerful enough to alter the influence of the sun, our orbit and perturbations of our alignment?
Is it based on the theory that agreement brings financial support and fame? There are too many axes being sharpened on this subject and and far too much of the "shoot the messenger" tactics.
The blogger referenced below is not up to speed on the latest findings. Researchers have found that some of the ocean temp sensors were sending bad data. Here is an article from a legitimate source (i.e. NASA, not a blog by a political hack) that provides the details:
http://earthobservatory.nasa.gov/Features/OceanCooling/printall.php
Maybe that is the reason for stronger winters and more rapid ice cover increases in the Arctic last autumns ?
climate chanced snow coverd snow lab in ice monthe
may 2011 - 1998
thank you ericbooth the weather net work
severe drught thunderstorms may be tornados
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