First, a clarification; while the AGU calls it an “ozone hole”, it technically isn’t. As NASA says here, it really isn’t a “hole” in the true sense of the word, it is simply a region of reduced O3 concentration that periodically changes in size, shape, and density. -Anthony
Ozone hole might slightly warm planet
AGU Release No. 13-39
WASHINGTON, DC—A lot of people mix up the ozone hole and global warming, believing the hole is a major cause of the world’s increasing average temperature. Scientists, on the other hand, have long attributed a small cooling effect to the ozone shortage in the hole.
Now a new computer-modeling study suggests that the ozone hole might actually have a slight warming influence, but because of its effect on winds, not temperatures. The new research suggests that shifting wind patterns caused by the ozone hole push clouds farther toward the South Pole, reducing the amount of radiation the clouds reflect and possibly causing a bit of warming rather than cooling.
“We were surprised this effect happened just by shifting the jet stream and the clouds,” said lead author Kevin Grise, a climate scientist at Lamont-Doherty Earth Observatory of Columbia University in New York City.
Grise notes this small warming effect may be important for climatologists trying to predict the future of Southern Hemisphere climate.
The work is detailed in Geophysical Research Letters, a journal of the American Geophysical Union. Grise collaborated on the study with Lorenzo Polvani of Columbia University, George Tselioudis of NASA Goddard Institute for Space Studies, Yutian Wu of New York University, and Mark Zelinka of Lawrence Livermore National Laboratory.
Hole in the sky
Each ozone molecule consists of three oxygen atoms bound together. These ozone molecules gather in the lower portion of the stratosphere about 20 to 30 kilometers (12 to 19 miles) above the ground—about twice as high as commercial airliners fly.
Thankfully for the living things below, this layer of ozone shields Earth from some of the hazardous ultraviolet radiation barraging the atmosphere. Unchecked, these ultraviolet rays can cause sunburns, eye damage and even skin cancer.
In the 1980s, scientists discovered thinning of the ozone layer above Antarctica during the Southern Hemisphere’s spring months. The cause of this “hole” turned out to be chlorofluorocarbons, such as Freon, from cooling systems, aerosols cans and degreasing solvents, which break apart ozone molecules. Even though the1987 Montreal Protocol banned these chlorofluorocarbons worldwide, the ozone hole persists decades later.
Many people falsely equate the ozone hole to global warming. In a 2010 Yale University poll, 61 percent of those surveyed believed the ozone hole significantly contributed to global warming. Additionally, 43 percent agreed with the statement “if we stopped punching holes in the ozone layer with rockets, it would reduce global warming”.
An actual consequence of the ozone hole is its odd effect on the Southern Hemisphere polar jet stream, the fast flowing air currents encircling the South Pole. Despite the ozone hole only appearing during the spring months, throughout each subsequent summer the high-speed jet stream swings south toward the pole.
“For some reason when you put an ozone hole in the Southern Hemisphere during springtime, you get this robust poleward shift in the jet stream during the following summer season,” said Grise. “People have been looking at this for 10 years and there’s still no real answer of why this happens.”
Cloud reflection
The team of scientists led by Grise wondered if the ozone hole’s impacts on the jet stream would have any indirect effects on the cloud cover. Using computer models, they worked out how the clouds would react to changing winds.
“Because the jet stream shifts, the storm systems move along with it toward the pole,” said Grise. “If the storm systems move, the cloud system is going to move with it.”
High- and mid-level clouds, the team discovered, traveled with the shifting jet stream toward the South Pole and the Antarctic continent. Low-level cloud coverage dropped in their models throughout the Southern Ocean. While modeling clouds is a difficult task due to the variety of factors that guide their formation and movement, Grise noted that observational evidence from the International Satellite Cloud Climatology Project, a decades-long NASA effort to map global cloud distributions, supports their theory of migrating cloud coverage.
When the cloud cover moves poleward, the amount of energy the clouds can reflect drops, which increases the amount of radiation reaching the ground. “If you shift the reflector poleward,” Grise explained, “you’ve moved it somewhere there is less radiation coming in.”
In 2007, the Intergovernmental Panel on Climate Change reported a direct cooling effect from the thinning ozone layer—specifically, a reduction of about 0.05 watts per square meter’s worth of energy reaching the ground. However, Grise and his colleagues estimated the indirect effect of the shifting cloud coverage to be an increase of approximately 0.2 watts per square meter. Their result not only suggests that warming rather than cooling would be taking place, but also that there’s a larger influence overall. Since the jet stream only shifts during the summer months, the warming only takes place in those months.
“Theoretically this net radiation input into the system should give some sort of temperature increase, but it’s unknown if that signal could be detected or what the magnitude of it would be,” said Grise. For comparison, worldwide, an average of about 175 watts per square meter reaches the ground from sunlight, according to the George Washington University Solar Institute.
Dennis Hartmann, an atmospheric scientist at the University of Washington in Seattle unrelated with the project, points out that since predicting cloud behavior is so challenging, the model used in Grise’s study could be underestimating clouds north of the jet stream being pulled toward the equator and in turn reflecting more light, potentially reducing or even negating the warming effect. Hartmann added that he also has some concerns about the modeling of the low-level cloud response.
Still, “this is certainly a very interesting topic and potentially important from a practical perspective of predicting Southern Hemisphere climate and even global warming rates,” he commented.
Climate tug-of-war
Looking toward the future, the jet stream should do less and less shifting to the south during the summer months as the ozone layer above the South Pole recovers. However, increasing levels of greenhouse gases can also change mid-latitude wind patterns and push the jet stream poleward, creating a complicated scenario which Grise said he plans to study in future work.
“You have sort of this tug-of-war between the jet being pulled equator-ward during the summer because of the ozone recovery and the greenhouse gases pulling the jet further poleward,” said Grise. “What the clouds do in that scenario is an open question.”
Funding for the research was provided by the National Science Foundation and by the U.S. Department of Energy’s Office of Science.
Notes for Journalists: Journalists and public information officers (PIOs) of educational and scientific institutions who have registered with AGU can download a PDF copy of this article by clicking on the following link:
http://onlinelibrary.wiley.com/doi/10.1002/grl.50675/abstract
Or, you may order a copy of the paper by emailing your request to Thomas Sumner. Please provide your name, the name of your publication, and your phone number.
Neither the paper nor this press release is under embargo.
Title:
The Ozone Hole Indirect Effect: Cloud-Radiative Anomalies Accompanying the Poleward Shift of the Eddy-Driven Jet in the Southern Hemisphere
Authors:
Kevin M. Grise: Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York, USA
Lorenzo M. Polvani: Department of Applied Physics and Applied Mathematics, and Department of Earth and Environmental Sciences, Columbia University, New York, New York, USA;
George Tselioudis: NASA Goddard Institute for Space Studies, New York, New York, USA;
Yutian Wu: Center for Atmosphere Ocean Science, Courant Institute of Mathematical Sciences, New York University, New York, New York, USA;
Mark D. Zelinka: Program for Climate Model Diagnosis and Intercomparison, Lawrence Livermore National Laboratory, Livermore, California, USA.
Contact information for the authors:
Kevin Grise, +1 (845) 735-3802, Email: kgrise@ldeo.columbia.edu
Lorenzo Polvani, +1 (212) 854-7331, Email: lmp@columbia.edu
If one looks at atmospheric circulation studies during the past two prolonged solar minimum (maunder and dalton) periods the conclusions are these periods of prolonged low solar activity result in a more meridional atmospheric circulation pattern.
Ozone is the key to the temperature profile of the atmosphere which in turn determines the atmospheric circulation patterns. End of story.
Still I want to hear from Henry, on this matter.
Henry while you are at it, give us a outlook for global temp. going forward and your reasoning.
I say they will be going down for the rest of this decade due to very low solar conditions and the secondary effects associated with this solar condition. What do you say?
HenryP says: August 9, 2013 at 10:34 am
The question is : where did you find ozone data from >45 km?
Much of the recent data I’ve seen is from below 45km, e.g.:
http://www.epa.gov/ozone/science/images/FIG-FAQ01.JPG
http://www.cpc.ncep.noaa.gov/products/stratosphere/polar/gif_files/sp_profile.gif
However this 2011 paper, “Twenty-two years observations of stratospheric ozone concentration,
temperature and aerosol over Tsukuba, Japan”
http://www-lidar.nies.go.jp/LRSJ/28thLSS/28th_papers/PG-34.pdf
included data above 45 KM data, as well as this 1999 paper “Relation between ozone and temperature in the Arctic stratosphere”;
http://www.agu.org/journals/ijga/v01/gai97140/gai97140.htm
here’s their Fig 1;
http://www.agu.org/journals/ijga/v01/gai97140/fig01.htm
this 1970 paper “An Explanation for the Worldwide Anomaly in the Concentration of Ozone above 40 km”;
http://journals.ametsoc.org/doi/pdf/10.1175/1520-0469%281970%29027%3C0968%3AAEFTWA%3E2.0.CO%3B2
as does this 1969 paper, a “Worldwide Anomaly in the Concentration of Ozone above 40 km”;
http://journals.ametsoc.org/doi/pdf/10.1175/1520-0469%281969%29026%3C0613%3AAWAITC%3E2.0.CO%3B2
and 1958 paper, “The Temperature Dependence of Ozone Radiational Heating Rates In The Vicinity of The Mesopeak” has 45km data:
http://journals.ametsoc.org/doi/pdf/10.1175/1520-0469%281958%29015%3C0059%3ATTDOOR%3E2.0.CO%3B2
Salvatore Del Prete says: @ur momisugly August 9, 2013 at 12:08 pm
If you look they use the bogus greenhouse gasses in this article. Had to get it in, and really takes away from this article, in my opinion.
>>>>>>>>>>>>>>>>
A nod to the Greenhouse Gas Gods is the necessary ‘Get Out of Jail Free’ card in most journals. Without it you do not get published.
From: Phil Jones. To: Many. March 11, 2003
“I will be emailing the journal to tell them I’m having nothing more to do with it until they rid themselves of this troublesome editor.”
From Phil Jones To: Michael Mann (Pennsylvania State University). July 8, 2004
“I can’t see either of these papers being in the next IPCC report. Kevin and I will keep them out somehow — even if we have to redefine what the peer-review literature is!”
They redefined it to mean Greenpeace and WWF propaganda pieces are ‘Science’ and papers by skeptics are not. UN’s Climate Bible Gets 21 “F”s on Report Card
Just The Facts.
Many thanks for those references.
The last one clearly suggests that temperatures are substantially governed by ozone amounts above 45km.
Couple that with the reverse sign ozone response above 45km and my propositions have ‘legs’.
Surely someone in authority can join the dots?
Barrie Sellers : ““The half life of ozone at -50degrees C is 3 months – there’s your ozone hole. As soon as the sun goes down. and the UV rays stop producing more ozone. the ozone hole gets bigger until the sun returns.”
This is one of the theories that comes up frequently but is simply disproved. The ozone hole does NOT form in winter. It forms in Spring when the sunlight returns. Most alternative theories fail on this point
As for diamagnetism/paramagnetism – those are very weak effects measurable only under laboratory conditions with magnetic fields much greater than that of the Earth. (Consult a book on Physical Chemistry if you doubt me). To prove any merit in this suggestion you would have to demonstrate that the effect is large enough to overcome the mixing of the atmosphere. Is there any evidence that this is possible?
One further comment on diamagnetic/paramagnetic. To clear up a confusion evident in some comments, molecules which are diamagnetic or paramagnetic are NOT drawn towards to poles of a magnet – they move in a direction perpendicular to the field.
And keep in mind that the swift shrinkage and re-expansion, etc., of the O-hole instantly disproved the Montreal Meme, that human-source CFCs control it.
Another KO for Natural Variation!
Can anybody tell me how to make a hole in the air? Atmosphere above both poles are thinner than above equator, there are no holes. Use common sense with centripetal / centrifugal force due to rotation of the earth and high / low tides of the sea due to pulling force of the moon.
I looked over Henry’s thoughts . They are not that bad although I do have areas of disagreement, but don’t we all.
The biggest area is his call for the temperature deceleration decline to begin to subside around years 2016-2019.
If solar activity turns out to be as severe as many of us are anticipating the cooling should be INCREASING going forward as this decade proceeds.
The biggest fault I have with many of the climatic outlooks is almost all of them fail to take into account possible thresholds that exist in our climatic systen(therefore none can address the abrupt climate changes of the past that have occurred on a regular basis) andmany of them are always trying to fit the climate into a neat regular rythmic cycle.
It does not work that way due to the following:
1. The beginning state of the climate has much to do with how the climate will change even if the same forcings are applied.
2. The climatic system is non linear which means the same forcings can produce a completly different result.
3. Even if one and two were not correct the location, the degree of magnitude of the forcings and the duration of time of the forcings and how many different forcings are phased into a cold regime or a warm regime at the same time would cause major differences in the evenual climatic outcome.
That is why these percise climatic outlooks like Henry is trying to do are estimates.
I can say with confidence that the temperature trends are going to be down at least until 2040 or so due to the very weak prolonged solar minimum and what past history has shown to be the climatic reaction to this type of an event.
However I don’t know the degree of magnitude or duration of time, the prolonged solar minimum will be, how much of an impact the weakening geo magnetic field will have,don’t know exactly how much volcanic activity may or may not be taken place going forward or the location, cosmic ray increases and their effects on clouds, and UV light decline impacts on ozone, and how meridional the atmospheric circulation may become and how long it may be sustained, or how this this circulation pattern may, or may not effect the thernmohaline circulation.
Let’s not forget a decline in solar visible light and how that will play upon ocean heat content going forward.
Then if this were not bad enough you have thresholds which are out there, which might be reached or may not be reached.
This is why( aside from co2 being a non climatic leader but rather a climatic result) the AGW model forecast are essentially uselss.
Nevertheless, through past evidence and current studies on solar/climatic relationships I can confidently conclude that the temperature trend will be down due to the prolonged solar minimum which started in earnest in late 2005.
My solar parameters(sustained following sub solar activity in general for several years) for minor temp decline are as follows:
solar flux sub 90
solar wind sub 350 km/sec
ap index 5-8
solar irradiance off .1 %
UV light off up to 25%
My solar parameters(sustained following sub solar activity in general for several years,which started in year 2005) for major temperature declines and even possible thresholds to come about are as follows:
solar flux sub 72 or lower
solar wind sub 300 km/sec or lower
ap index sub 5
solar irradiance off .2% or more
uv light emissions off upwards of 50%
None of the above has happened since the solar Dalton Minimumon a sustained basis following many years of sub solar activity.
This decade with the first prolonged solar minmium since the Dalton Minimum offers us an opportunity to see just how much or how little of an impact certain solar parameters will have on the climate in general.
Again because of the reasons given earlier the exact impacts are impossible to quantify.
If one looks at the aao index from 1979 to present the trend is there is no trend.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
1979 0.209 0.356 0.899 0.678 0.724 1.700 2.412 0.546 0.629 0.160 -0.423 -0.951
1980 -0.447 -0.980 -1.424 -2.068 -0.479 0.286 -1.944 -0.997 -1.701 0.577 -2.013 -0.356
1981 0.231 0.039 -0.966 -1.462 -0.344 0.352 -0.986 -2.118 -1.509 -0.260 0.626 1.116
1982 -0.554 0.277 1.603 1.531 0.118 0.920 -0.415 0.779 1.580 -0.702 -0.849 -1.934
1983 -1.340 -1.081 0.166 0.149 -0.437 -0.263 1.114 0.792 -0.696 1.193 0.727 0.475
1984 -1.098 -0.544 0.251 -0.204 -1.237 0.426 0.890 -0.548 0.327 -0.009 -0.024 -1.476
1985 -0.795 0.215 -0.134 0.031 -0.066 -0.331 1.914 0.595 1.507 0.471 1.085 1.240
1986 0.158 -1.588 -0.770 -0.087 -1.847 -0.619 0.089 -0.157 0.849 0.306 -0.222 0.886
1987 -0.950 -0.708 -0.133 -0.286 0.039 -0.702 -1.531 1.485 -0.799 0.455 1.060 0.272
1988 -0.612 0.551 -0.219 -0.077 -0.749 -1.055 0.576 -0.745 -0.689 -2.314 0.401 1.074
1989 0.618 0.849 0.632 -0.573 2.691 1.995 1.458 -0.132 -0.121 0.136 0.572 -0.445
1990 -0.352 1.151 0.414 -1.879 -1.803 0.093 -1.215 0.466 1.482 0.139 -0.359 -0.312
1991 0.869 -0.852 0.522 -0.639 -0.539 -1.155 -1.220 0.036 -0.513 -0.623 -0.804 -2.067
1992 0.073 -1.627 -1.010 -0.439 -2.032 -2.193 -0.566 -0.350 0.435 -0.319 0.122 0.244
1993 -2.021 0.437 -0.378 0.087 1.260 1.218 1.957 1.083 1.061 0.748 0.324 1.028
1994 0.723 1.157 0.693 -0.052 -0.153 -1.682 -0.492 1.910 -0.947 -0.578 -0.793 0.933
1995 1.448 0.533 -0.154 0.649 1.397 -0.802 -3.010 -0.696 1.173 -0.057 0.143 1.470
1996 0.332 -0.525 0.543 0.115 0.983 -0.252 0.021 -1.502 -1.314 0.966 -1.667 -0.023
1997 0.369 -0.244 0.701 -0.458 1.028 -0.458 0.780 0.768 0.122 -0.595 -1.905 -0.835
1998 0.413 0.390 0.736 1.927 -0.038 1.031 1.450 0.904 -0.122 0.400 0.817 1.435
1999 0.999 0.456 0.180 0.949 1.639 -1.325 0.316 0.042 -0.012 1.653 0.901 1.784
2000 1.273 0.620 0.133 0.233 1.127 0.117 0.059 -0.674 -1.853 0.347 -1.537 -1.290
2001 -0.471 -0.265 -0.555 0.515 -0.262 0.386 -0.928 0.910 1.161 1.277 0.996 1.474
2002 0.747 1.334 -1.823 0.165 -2.798 -1.112 -0.591 -0.099 -0.864 -2.564 -0.924 1.308
2003 -0.988 -0.357 -0.188 0.224 0.385 -0.775 0.727 0.678 -0.323 -0.025 -0.712 -1.323
2004 0.807 -1.182 0.432 0.151 0.460 1.195 1.474 -0.071 0.254 -0.042 -0.242 -0.973
2005 -0.129 1.243 0.158 0.355 -0.297 -1.428 -0.252 0.228 0.241 0.031 -0.551 -1.968
2006 0.339 -0.211 0.501 -0.169 1.695 0.438 0.926 -1.727 -0.324 0.879 0.101 0.638
2007 -0.083 0.075 -0.570 -1.035 -0.612 -1.198 -2.631 -0.108 0.031 -0.434 -0.984 1.929
2008 1.208 1.147 0.587 -0.873 -0.490 1.348 0.320 0.087 1.386 1.215 0.920 1.194
2009 0.963 0.456 0.605 0.029 -0.733 -0.470 -1.234 -0.686 -0.017 0.085 -1.915 0.607
2010 -0.757 -0.775 0.108 0.377 1.021 2.071 2.424 1.510 0.402 1.335 1.516 0.205
2011 0.052 1.074 -0.296 -0.870 1.266 -0.099 -1.384 -1.202 -1.250 0.388 -0.908 2.573
2012 1.583 -0.283 0.275 0.666 0.153 -0.197 1.259 0.489 0.562 -0.444 -1.701 -0.764
2013 0.071 0.716 1.375 0.611 0.360 -0.271 0.945