Extreme weather and climate change: a new IPCC report

By: Dr. Jeff Masters , 3:48 PM GMT on November 18, 2011

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Extreme weather events are already being affected by human-caused climate change, and will increase in destructive power during the coming decades as huge cost, reported the United Nations Intergovernmental Panel on Climate Change (IPCC) today. The IPCC issues reports on the state of the scientific knowledge of climate change every six years, with the next full report due out in 2013. However, concern over the possible impact climate change may already be having on extreme weather events like heat waves, floods, and droughts prompted the IPCC to release their first-ever Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX). The SREX report was divided into two sections: how human-caused climate change has already affected extreme weather events, and predictions on how these events will change during the rest of the century. Here are some highlights on how the climate has already changed, according to the SREX report:

- Globally, cold days and nights have decreased, and warm days and nights have increased (90 - 100% chance).

- In many but not all regions of the globe, the length or number of heat waves has increased.

- Some areas have seen more intense and longer droughts, in particular, southern Europe and West Africa. However, droughts have become less frequent, less intense, or shorter in some areas, such as central North America and northwestern Australia.

- Heavy precipitation events have changed in some regions. There is at least a 2-in-3 probability that more regions have seen increases than decreases in heavy precipitation events.

- The historical data base on hurricanes and tropical cyclones is not good enough to tell if they have changed.

- The jet stream has shifted towards the poles, meaning that the tracks of rain-bearing low pressure systems have also shifted towards the poles.

- Rising sea levels have led to an increase in extreme coastal flooding events (66 - 100% chance).

- Damage from extreme weather events has increased. Increases in population and wealth, and the fact more people are living in vulnerable areas, is a major cause of this increase in damage. It is uncertain if climate change is partially responsible for the increase in damage.


Figure 1. Predicted return periods for 1-day extreme precipitation events that occurred, on average, only once every 20 years between 1981-2000. A decrease in return period implies more frequent extreme precipitation events (i.e., less time between events on average). For Eastern North America, a 1-in-20 year heavy rain event is predicted to become a 1-in-7 to 1-in-9 year event by the end of the century, according to these climate model predictions. The box plots show results for regionally averaged projections for two time horizons, 2046 to 2065 and 2081 to 2100, as compared to the late-20th-century, and for three different emissions scenarios--a scenario where humans emit relatively little CO2 and other heat-trapping gasses (B1, blue bars), and two higher-emission scenarios (A1B and A2, green and red bars). Humanity is currently on a pace to emit more CO2 than the highest emission scenario shown here. Results are based on 14 climate models that contributed to the 2007 IPCC report. The level of agreement among the models is indicated by the size of the colored boxes (in which 50% of the model projections are contained), and the length of the whiskers (indicating the maximum and minimum projections from all models). Values are computed for land points only. The “Globe” inset box displays the values computed using all land grid points. Averaged over all areas of the globe, a 1-in-20 year heavy rain event is predicted to become a 1-in-8 to 1-in-12 year event by the end of the century. Image credit: The IPCC Special Report on Managing the Risks of Extreme Events and Disasters (SREX), 2011.

Here are some highlights of the forecasts for the future from the 2011 SREX report:

- A 1-in-20 year hottest day is at least 66% likely to become a 1-in-2 year event by the end of the 21st century in most regions, except in the high latitudes of the Northern Hemisphere, where it is likely to become a 1-in-5 year event.

- For Eastern North America, a 1-in-20 year heavy rain event is predicted to become a 1-in-7 to 1-in-9 year event by the end of the century.

- For Eastern North America, a maximum high temperature that occurred only once every 20 years during 1980 - 2000 is predicted to occur between once every three years and once per year by 2100.

- Extreme high temperature readings that occur once every 20 years will increase by 1°C to 3°C (1.8°F - 5.4°F) by mid-21st century and by about 2°C to 5°C (3.6°F - 9°F) by late-21st century.

- It is at least 66% likely that the frequency of heavy precipitation or the proportion of total rainfall from heavy falls will increase in the 21st century over many areas of the globe. This is particularly the case in the high latitudes and tropical regions, and in winter in the northern mid-latitudes. There is medium confidence that, in some regions, increases in heavy precipitation will occur despite projected decreases of total precipitation in those regions.

- Heavy rainfalls associated with tropical cyclones are at least 66% likely to increase with continued warming, and the maximum winds will increase. The total number of these storms is likely to remain about the same or decrease.

- There is medium confidence that droughts will intensify in the 21st century in some seasons and areas. Southern Europe and the Mediterranean region, central Europe, Central North America, Central America and Mexico, northeast Brazil, and southern Africa are at particular risk.

- In some regions, the main driver for increased damages from extreme weather events will not be climate change, but increases in population and wealth and vulnerability.

Intoducing climatecommunication.org
For those of you seeking detailed information on the research linking extreme weather events to climate change, I recommend a new website dedicated to improving communication of climate change information to the public, media, and policy makers, climatecommunication.org. The group is led by Susan Joy Hassol, a veteran climate change communicator, analyst, and author known for her ability to translate science into English, making complex issues accessible to policymakers and the public. Climatecommunication.org has put together an overview of extreme weather and climate change that I find a helpful resource when I am looking for the latest research results on the subject. I serve on their advisory board, along with a number of leading climate scientists.


Figure 2. Still image of the Bangkok, Thailand floods of October - November, 2011, as seen on the inaugural episode our new bi-monthly Extreme Weather video series.

Wunderground launches new Extreme Weather video series
Wunderground now features a new, twice-monthly Extreme Weather video series from GREEN.TV, with the latest reports and analysis on extreme weather around the world. From droughts to hurricanes to blizzards to flooding, Extreme Weather will cover the story and the science behind the events to try to understand their causes and consequences. The Extreme Weather series is sponsored by Vestas, the world's leading wind turbine manufacturer. The inaugural episode, launched yesterday, features video of the great Thailand flood, destructive floods in Italy, the $3 billion Northeast U.S. snowstorm of October 29 - 30, the massive Bering Sea, Alaska blizzard of November 9, the Texas drought, and the launch of a new polar-orbiting weather satellite. Look for a new video every two weeks on our Climate Change Videos page.

Resources
For those of you who haven't seen it, my top "must-read" post of 2011 is called, 2010 - 2011: Earth's most extreme weather since 1816?. Back in June, I went through the ridiculous barrage of extreme weather events the planet saw in 2010 and early 2011, and concluded: But it is highly improbable that the remarkable extreme weather events of 2010 and 2011 could have all happened in such a short period of time without some powerful climate-altering force at work. The best science we have right now maintains that human-caused emissions of heat-trapping gases like CO2 are the most likely cause of such a climate-altering force.

Wunderground's climate change blogger, Dr. Ricky Rood, has some thoughtful observations on the communication of the extreme weather/climate change link published in earthzine magazine titled, Changing the Media Discussion on Climate Change and Extreme Weather.

Jeff Masters

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412. BahaHurican
1:58 AM GMT on November 20, 2011
Quoting CaicosRetiredSailor:
Looks like I will be in Jamaica for a brief trip (mainly to the Kingston area) soon. My first visit there and I am looking forward to it. I'll have my iPad with me so will check in from the Big Island... Years back, Turks and Caicos was ruled under the Govenor in Jamaica.
That is some years back.... lol. I've never been to JA, though I did spend a couple weeks in PR some years back.

The rain seems to have given up for now.... but it's now warmed up a bit... not quite sure what wx factor would cause that... the back end of a front????

Member Since: October 25, 2005 Posts: 19 Comments: 22682
411. j2008
1:56 AM GMT on November 20, 2011
Quoting AstroHurricane001:


That looks like one elongated trough, creating a hole in the subtropic central-eastern portion of the Bermuda-Azores High. This might become a quasi-permanent structure for the next two weeks.

That should be fun to monitor, especially if it does what the GFS was wanting. 3 TC's over the next couple weeks, not hitting land so basically the good type of storm. Thanks for the opinion Astro.
Member Since: December 19, 2008 Posts: 1 Comments: 224
410. SPLbeater
1:53 AM GMT on November 20, 2011
and part of the reason, is these media stations (The Weather Channel being one) think that a location is warm because the forecasted high temperature is +2 above average. the temperatures are never going to be average every single day, because the weather is never the same each year, each week, each day. i wouldnt call it warmer then average unless it was over +10. I have recently quit listening to all the media stations and put my full attention to NOAA(and their branches NHC, NWS, and SPC of course lol) because they dont give any of that crap. they give you the forecast and more stuff for us weather junkies.
Member Since: August 4, 2011 Posts: 46 Comments: 4488
409. SPLbeater
1:49 AM GMT on November 20, 2011
Quoting stormstorm:
weather underground needs to change the name of this blog to the GREAT GLOBAL WARMING DEBATE BLOG after the end of the hurricane season, cause thats all everyone talks about. although it has some meaning in the whole scheem of things in the tropics its completley off topic. could start 2 seperate blogs with the other being severe weather or noreasters.....just my 2 cents worth..dont get to excited....  yes i know i cant spell..good day


I TOTALLY AGREE WITH YOU. mostly for the fact global warming has the word myth all over it. buncha scientists getting excited of half a degree incline in average tempatures, blah
Member Since: August 4, 2011 Posts: 46 Comments: 4488
408. AstroHurricane001
1:46 AM GMT on November 20, 2011
Quoting j2008:

I highly doubt that it was labled, I dont think they have found a COC/LLC anywhere in the blob that is sustaining convection and is worthy of an invest lable. IMO it shouldnt be to much longer till we get one though.


That looks like one elongated trough, creating a hole in the subtropic central-eastern portion of the Bermuda-Azores High. This might become a quasi-permanent structure for the next two weeks.
Member Since: August 30, 2008 Posts: 8 Comments: 2835
407. j2008
1:44 AM GMT on November 20, 2011
Quoting stormstorm:
weather underground needs to change the name of this blog to the GREAT GLOBAL WARMING DEBATE BLOG after the end of the hurricane season, cause thats all everyone talks about. although it has some meaning in the whole scheem of things in the tropics its completley off topic. could start 2 seperate blogs with the other being severe weather or noreasters.....just my 2 cents worth..dont get to excited....  yes i know i cant spell..good day

In a couple days I might start doing blogs on weather happening right now, as in TC's and other weather, those of us that wanna talk about that can mosey on over there when I get around to it..... SO... Kenneth should be here tonight or tomorrow morning at latest, and a 40% also in the Atlantic this evening. I expect STS Tammy by ohh say maybe Monday night at earlyest. Feedback anyone??
Member Since: December 19, 2008 Posts: 1 Comments: 224
406. stormstorm
1:37 AM GMT on November 20, 2011
weather underground needs to change the name of this blog to the GREAT GLOBAL WARMING DEBATE BLOG after the end of the hurricane season, cause thats all everyone talks about. although it has some meaning in the whole scheem of things in the tropics its completley off topic. could start 2 seperate blogs with the other being severe weather or noreasters.....just my 2 cents worth..dont get to excited....  yes i know i cant spell..good day
Member Since: October 16, 2011 Posts: 0 Comments: 7
405. AstroHurricane001
1:30 AM GMT on November 20, 2011
I detected the off-topic word "religious" in above comments. Alrighty then.

During my research on environmental issues, I found this publication from 1993: Guernsey, D., & Stanton, M. (1993). Christians’ Ecological Responsibility: A Theological Introduction and Challenge. The American Scientific Affiliation
Member Since: August 30, 2008 Posts: 8 Comments: 2835
404. CaicosRetiredSailor
1:28 AM GMT on November 20, 2011
Looks like I will be in Jamaica for a brief trip (mainly to the Kingston area) soon. My first visit there and I am looking forward to it. I'll have my iPad with me so will check in from the Big Island... Years back, Turks and Caicos was ruled under the Govenor in Jamaica.
Member Since: July 12, 2007 Posts: 0 Comments: 6069
403. TropicalAnalystwx13
1:22 AM GMT on November 20, 2011
Quoting Skyepony:
13E is up to a 2.1 with a raw score of 3.5.

May be Kenneth at the 7PM PST update.
Member Since: July 6, 2010 Posts: 113 Comments: 32692
402. CaicosRetiredSailor
1:21 AM GMT on November 20, 2011
Quoting BahaHurican:
Evening everyone. We're getting rain here right now, and have been, off and on, for the last 1/2 hour or so. Rather heaviery thatn one is used to in November, and much heaviere than oune would expect base on the image below.


Interestingly, I had the same experience today, total overcast some heavy rain, and no cold cloud tops showing at all on the Sat image...
Member Since: July 12, 2007 Posts: 0 Comments: 6069
401. Skyepony (Mod)
1:17 AM GMT on November 20, 2011
13E is up to a 2.1 with a raw score of 3.5.
Member Since: August 10, 2005 Posts: 208 Comments: 39074
It will start off as Subtropical Storm Tammy judging by Satellite imagery.

Member Since: July 6, 2010 Posts: 113 Comments: 32692
399. Skyepony (Mod)
Major storms could submerge New York City in next decade

Sea-level rise due to climate change could cripple the city in Irene-like storm scenarios, new climate report claims.
Member Since: August 10, 2005 Posts: 208 Comments: 39074
No change in SAB/TAFB since the last update --

19/2345 UTC 10.1N 101.4W T2.0/2.0 13E -- East Pacific
Member Since: July 6, 2010 Posts: 113 Comments: 32692
Quoting BahaHurican:
Evening everyone. We're getting rain here right now, and have been, off and on, for the last 1/2 hour or so. Rather heaviery thatn one is used to in November, and much heaviere than oune would expect base on the image below.


Torrential rain here in the North of the Island again today. Trinidad.
Flooding in parts of the City (Port-of-Spain) and in the Diego Martin and Maraval valleys.
Traffic snarled-up for up to 4 hrs in places with roads closed and walls down.

A series of very heavy, but isolated downpours over the past couple weeks have caused real problems all over the Island.

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Quoting TropicalAnalystwx13:

The only hype I've heard over a Tuesday Severe Weather Outbreak is from you.
(No offense meant)


no offense taken. except from those 3 who plused that. few people been posting models showing a forecasted outbreak, they know who they are
Member Since: August 4, 2011 Posts: 46 Comments: 4488
Evening everyone. We're getting rain here right now, and have been, off and on, for the last 1/2 hour or so. Rather heaviery thatn one is used to in November, and much heaviere than oune would expect base on the image below.

Member Since: October 25, 2005 Posts: 19 Comments: 22682
Quoting Ameister12:
TD 13 is looking nice tonight.


I also noticed that the NHC has brought out the orange crayon.



your a little too late
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Quoting yqt1001:


99L was Rolf, 98L was Sean.





will have to wait and see then
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TD 13 is looking nice tonight.


I also noticed that the NHC has brought out the orange crayon.
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Quoting Tazmanian:




it would be 99L has 98L was are last one


99L was Rolf, 98L was Sean.
Member Since: November 19, 2010 Posts: 1 Comments: 1286
Quoting Tazmanian:




it would be 99L has 98L was are last one

Well yeah, but I was agreeing with the part that it would eventually become Tammy.
Member Since: July 6, 2010 Posts: 113 Comments: 32692
Quoting TropicalAnalystwx13:

I agree.




it would be 99L has 98L was are last one
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Quoting HuracanTaino:
If moving northward to cooler waters, probably subtropical in nature....

Yes, of course. However, that doesn't mean it can't transition into a tropical storm, especially since this disturbance is currently situated farther to the south than Sean was, and it was able to attain strong tropical storm or minimal hurricane status.
Member Since: July 6, 2010 Posts: 113 Comments: 32692
Quoting TropicalAnalystwx13:

Code Orange!
If moving northward to cooler waters, probably subtropical in nature....
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At first, I didn't know what low pressure area they were talking about. However, if you look closely on satellite imagery loops, you can see the beginnings of an area of rotation.
Member Since: July 6, 2010 Posts: 113 Comments: 32692
Quoting Stormchaser2007:
Brandy new 1008mb low.

Should be 90L soon and Tammy later.


I agree.
Member Since: July 6, 2010 Posts: 113 Comments: 32692
Member Since: Posts: Comments:
Brandy new 1008mb low.

Should be 90L soon and Tammy later.

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Quoting WeatherNerdPR:
000
ABNT20 KNHC 192331
TWOAT

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
700 PM EST SAT NOV 19 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

SATELLITE IMAGERY AND SURFACE OBSERVATIONS INDICATE THAT A BROAD LOW
PRESSURE AREA HAS FORMED OVER THE CENTRAL ATLANTIC OCEAN ABOUT
700 MILES NORTHEAST OF THE LEEWARD ISLANDS. WHILE THE ASSOCIATED
CLOUDINESS AND SHOWERS ARE POORLY ORGANIZED...CONTINUED SLOW
DEVELOPMENT OF THIS SYSTEM IS POSSIBLE DURING THE NEXT COUPLE OF
DAYS AS IT MOVES SLOWLY NORTHWARD. THERE IS A MEDIUM CHANCE...
30 PERCENT...OF SUBTROPICAL OR TROPICAL CYCLONE FORMATION FROM THIS
SYSTEM DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER BEVEN

Code Orange!
Member Since: July 6, 2010 Posts: 113 Comments: 32692
000
ABNT20 KNHC 192331
TWOAT

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
700 PM EST SAT NOV 19 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

SATELLITE IMAGERY AND SURFACE OBSERVATIONS INDICATE THAT A BROAD LOW
PRESSURE AREA HAS FORMED OVER THE CENTRAL ATLANTIC OCEAN ABOUT
700 MILES NORTHEAST OF THE LEEWARD ISLANDS. WHILE THE ASSOCIATED
CLOUDINESS AND SHOWERS ARE POORLY ORGANIZED...CONTINUED SLOW
DEVELOPMENT OF THIS SYSTEM IS POSSIBLE DURING THE NEXT COUPLE OF
DAYS AS IT MOVES SLOWLY NORTHWARD. THERE IS A MEDIUM CHANCE...
30 PERCENT...OF SUBTROPICAL OR TROPICAL CYCLONE FORMATION FROM THIS
SYSTEM DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER BEVEN
Member Since: Posts: Comments:
The tornadoes earlier this week brought the 2011 death toll in the USA from tornadoes up to 553. This is the second highest death toll in the USA. 1925 is higher with 794 deaths. 1936 previously held second place with 552 deaths. 1936 is also the only year on record in which two separate tornadoes each killed more than 200 people.
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Quoting Seastep:


First, OSHA is 5000ppm, and that is indoors where it is being artificially trapped.

Second, I had to go through this a few years ago with someone also. Stop the silliness.

Do you realize what the atmospheric ppm, as measured at Mauna Loa has to bee to get that kind of concentration on the ground?

It's silly to even discuss. It is not toxic unless you are a mountain climber. Period.

It is a colorless, odorless, harmless gas in that context.

Feel free to actually believe we can pump enough CO2 into the atmosphere for it actually to be toxic on the ground. But, that would be silly.


OSHA, and the EPA, sets indoor exposure levels based on the ppm for CO2 and the duration of time spent at those levels. OSHA, and the EPA, assumes that you will be able to get outdoors into the now normal atmospheric concentration of 300-400 ppm of atmospheric CO2 levels. Once the atmospheric concentration of CO2 exceeds 400 ppm, then I believe it is safe to say that OSHA, and the EPA, will have to reevaluate these exposure levels and the time spent at these levels.

I do agree with you that there is absolutely no chance that atmospheric CO2 levels will ever approach 50,000 ppm. I believe that there are enough carbon and oxygen atoms available to form that level of atmospheric CO2 concentration but, any human presence would long be gone before our activities could force such a concentration. I also agree that you should stop your silliness.
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Quoting SPLbeater:
how is it all this hype of a severe outbreak on tuesday, yet the SPC has 'no area' potential too low for tuesday? lol.

The only hype I've heard over a Tuesday Severe Weather Outbreak is from you.
(No offense meant)
Member Since: July 6, 2010 Posts: 113 Comments: 32692
how is it all this hype of a severe outbreak on tuesday, yet the SPC has 'no area' potential too low for tuesday? lol.
Member Since: August 4, 2011 Posts: 46 Comments: 4488
Quoting yqt1001:
Deep convection over 13E's center finally.


These estimates are from 1745 UTC, before the depression was classified, so they are likely higher at this time. Eighteen-E is gradually organizing, and the next update isn't until 7 PM PST, so I believe we may have Kenneth at the next update.

19/1745 UTC 9.9N 100.5W T2.0/2.0 90E -- East Pacific
Member Since: July 6, 2010 Posts: 113 Comments: 32692
Deep convection over 13E's center finally.

Member Since: November 19, 2010 Posts: 1 Comments: 1286
.
Member Since: July 6, 2010 Posts: 113 Comments: 32692
Quoting NCHurricane2009:
Looks like the E-pac is getting attention....

Can someone answer if the disturbance in the Central Atlantic was Invest 90-L? I thought I saw it being declared yesterday afternoon...now its not declared as an Invest....
Probably it deserves a classiication briefly yesterday, but to much dry air in that area, and now the naked swirl is heading SW, towards the hot waters of the northern antilles, but as a non entity.... I guess...
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Quoting sar2401:


Galactic cosmic rays? I don't understand why higher dewpoints would make condensation less likely. Desert areas are characterized by very low dewpoints and tropical climates are characterized by high dewpoints, with plenty of condensation.
lower dewpoints* my bad
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Quoting trHUrrIXC5MMX:
BASED ON HISTORICAL RECORDS...TROPICAL DEPRESSION THIRTEEN-E IS THE
LATEST-FORMING TROPICAL CYCLONE IN THE EASTERN NORTH PACIFIC BASIN
SINCE TROPICAL DEPRESSION TWENTY-TWO-E IN 1987...WHICH FORMED ON
NOVEMBER 24. IF IT BECOMES A TROPICAL STORM...IT WOULD BE THE
LATEST-FORMING NAMED STORM SINCE HURRICANE WINNIE IN 1983...WHICH
FORMED ON DECEMBER 4.

FORECAST POSITIONS AND MAX WINDS

INIT 19/2100Z 10.0N 101.0W 30 KT 35 MPH
12H 20/0600Z 10.2N 102.5W 35 KT 40 MPH
24H 20/1800Z 10.9N 104.5W 40 KT 45 MPH
36H 21/0600Z 11.4N 106.8W 45 KT 50 MPH
48H 21/1800Z 11.6N 109.0W 50 KT 60 MPH
72H 22/1800Z 12.0N 113.0W 60 KT 70 MPH
96H 23/1800Z 12.5N 118.0W 65 KT 75 MPH
120H 24/1800Z 13.5N 122.5W 55 KT 65 MPH

TD 13 can make into the CP?

Hurricane Winnie?
Hurricane winnie the pooh
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Quoting Snowlover123:
I have shown with observational evidence that the change in the Cloud Forcing has resulted in 7 w/m^2 being added to Earth's Energy Budget over a 21 year timeframe, compared to CO2 adding 1.4 w/m^2 since 1790 to Earth's Energy Budget.

This is one huge mistake that Spencer makes in a nutshell: there is no such thing as "cloud forcing" (with the exception of a small portion related to human aerosol effects effects, which have only a small effect on clouds). He assumes that ENSO responds to changes in cloud over, when it's clearly the other way around. On that alone, his entire argument is invalid.
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Quoting TomTaylor:
What's a GCR? and why does radiative flux allow us to rule out temperature? Temperatures have been found to be increasing throughout the troposphere, which raises dew points, making condensation harder. How does radiative flux make this not true/not a factor?


Galactic cosmic rays? I don't understand why higher dewpoints would make condensation less likely. Desert areas are characterized by very low dewpoints and tropical climates are characterized by high dewpoints, with plenty of condensation.
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368. j2008
Quoting NCHurricane2009:


I was thinking the cloud swirl tracking SW in direction of NE Caribbean (seen now in visible imagery) may have been Invest 90-L briefly yesterday...

Anyway...thanx for the answer...usually I am on top of these things...but I have been so busy this year with other matters that I could not track the 2011 Atlantic Season as closely....I will be much more involved during 2012...
Same here, I should be posting alot more in 2012 maybe even try to write some of my own blogs. Ohh...and no problem happy to help.
Member Since: December 19, 2008 Posts: 1 Comments: 224
Quoting Snowlover123:


By looking at the radiative flux changes with CERES, we can definitely rule out the decrease in Cloud albedo due to temperature because of the way the total radiative flux looks. It looks nothing like the radiative feedback. Moreso, a change in the Cloud Forcing due to an external factor, such as GCRs.

Humans have been adding ADDITIONAL aerosoles to the atmosphere, so if the albedo change COULD be due to human activity, the albedo should be going up, not going down. Sure, perhaps human activity could have slowed the decline in GCC slightly, but that's about as high as you can go.

What could possibly be the cause of the decrease in Cloud Cover?

The GCR hypothesis was developed by Physicist Dr. Henrik Svensmark, and looking at all of the evidence available, there is pretty good evidence that GCRs have caused at least some changes in the Cloud Cover.

Take this paper, which shows that GCRs have a significant impact on the diurnal temperature range during FDs, when they have the most evident effect on Climate.

They found that within a few days of the Forbush Decrease, (which is a small lag) the diurnal temperature substantially deviates from the normal diurnal temperature mean.

The diurnal temperature mean can be best described as the difference between the daytime and nightime temperatures.

The reason for why the diurnal temperature range would increase right after a FD, indicates not only that GCRs can influence the atmospheric processes on Earth substantially, but they also do so through Cloud Cover changes.

A sudden reduction in GCRs would substanitally lower Cloud Cover for those few days, which would substantially increase the difference in nighttime and daytime temperatures, since Clouds reflect ISR and trap OLR, reducing the diurnal temperature range.

http://www.astrophys-space-sci-trans...7-315-2011 .pdf




Quoting Paper


The result strongly supports the idea that
cosmic rays influence the atmospheric processes and climate.
----------


Or take this paper, which also finds a strong correlation between FDs and Global aerosoles, the "seeds" for the Clouds.

http://www.deas.harvard.edu/climate/eli/Courses/F RSEMR22l/Sources/03-Cosmic-rays/3-Svensmark-et-al- 2009-GRL.pdf




The dashed line is the GCR count and the solid blue line is the aerosol number. A short lag in Global aersoles can clearly be seen right after a Forbush Decrease, which indicates a significant CR-Influence on climate, if Forbush Decreases can have that much of an impact on aerosoles.


Or take this paper which shows a strong correlation between GCRs and Mid Latitude Clouds.



http://www.atmos-chem-phys.net/10/10941/2010/acp- 10-10941-2010.pdf

Quote:
The influence of GCRs is clearly distinguishable from changes in solar irradiance and the interplanetary magnetic field. However, the results of the GCM experiment are found to be somewhat limited by the ability of the model to successfully reproduce observed cloud cover. These results provide perhaps the most compelling evidence presented thus far of a GCR-climate relationship. From this analysis we conclude that a GCR-climate relationship is governed by both short-term GCR changes and internal atmospheric precursor conditions.
------------

Or take this study which highlights GCRs being a "plausable" Climate Driver:


http://cc.oulu.fi/~usoskin/personal/usoskin_CR_20 08.pdf


Quote:
In conclusion, a CR%u2013climate link seems to be a
plausible climate driver, as supported by the bulk of
statistical studies and existing theoretical models.
----------



Low Level Cloud Cover and GCRs for Europe as presented by Usoskin et. al 2008.


What's a GCR? and why does radiative flux allow us to rule out temperature? Temperatures have been found to be increasing throughout the troposphere, which lowers dew points, making condensation harder. How does radiative flux make this not true/not a factor?
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Quoting j2008:

I highly doubt that it was labled, I dont think they have found a COC/LLC anywhere in the blob that is sustaining convection and is worthy of an invest lable. IMO it shouldnt be to much longer till we get one though.


I was thinking the cloud swirl tracking SW in direction of NE Caribbean (seen now in visible imagery) may have been Invest 90-L briefly yesterday...

Anyway...thanx for the answer...usually I am on top of these things...but I have been so busy this year with other matters that I could not track the 2011 Atlantic Season as closely....I will be much more involved during 2012...
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Well I have to go, so I will enjoy to see more responses later.
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting TomTaylor:
Your entire argument just begs the question, what is causing the decrease in cloud cover? Aerosols, temperature, and humidity are the main factors affecting cloud formation. The only thing known to be consistently and currently influencing these factors over the last few decades is man. I suppose you could blame it on some sort of natural cycle, but there's no evidence for what this cycle is and it doesn't refute the idea that humans have altered the temperature and aerosol content of the atmosphere.


By looking at the radiative flux changes with CERES, we can definitely rule out the decrease in Cloud albedo due to temperature because of the way the total radiative flux looks. It looks nothing like the radiative feedback. Moreso, a change in the Cloud Forcing due to an external factor, such as GCRs.

Humans have been adding ADDITIONAL aerosoles to the atmosphere, so if the albedo change COULD be due to human activity, the albedo should be going up, not going down. Sure, perhaps human activity could have slowed the decline in GCC slightly, but that's about as high as you can go.

What could possibly be the cause of the decrease in Cloud Cover?

The GCR hypothesis was developed by Physicist Dr. Henrik Svensmark, and looking at all of the evidence available, there is pretty good evidence that GCRs have caused at least some changes in the Cloud Cover.

Take this paper, which shows that GCRs have a significant impact on the diurnal temperature range during FDs, when they have the most evident effect on Climate.

They found that within a few days of the Forbush Decrease, (which is a small lag) the diurnal temperature substantially deviates from the normal diurnal temperature mean.

The diurnal temperature mean can be best described as the difference between the daytime and nightime temperatures.

The reason for why the diurnal temperature range would increase right after a FD, indicates not only that GCRs can influence the atmospheric processes on Earth substantially, but they also do so through Cloud Cover changes.

A sudden reduction in GCRs would substanitally lower Cloud Cover for those few days, which would substantially increase the difference in nighttime and daytime temperatures, since Clouds reflect ISR and trap OLR, reducing the diurnal temperature range.

http://www.astrophys-space-sci-trans...7-315-2011 .pdf




Quoting Paper


The result strongly supports the idea that
cosmic rays influence the atmospheric processes and climate.
----------


Or take this paper, which also finds a strong correlation between FDs and Global aerosoles, the "seeds" for the Clouds.

http://www.deas.harvard.edu/climate/eli/Courses/F RSEMR22l/Sources/03-Cosmic-rays/3-Svensmark-et-al- 2009-GRL.pdf




The dashed line is the GCR count and the solid blue line is the aerosol number. A short lag in Global aersoles can clearly be seen right after a Forbush Decrease, which indicates a significant CR-Influence on climate, if Forbush Decreases can have that much of an impact on aerosoles.


Or take this paper which shows a strong correlation between GCRs and Mid Latitude Clouds.



http://www.atmos-chem-phys.net/10/10941/2010/acp- 10-10941-2010.pdf

Quote:
The influence of GCRs is clearly distinguishable from changes in solar irradiance and the interplanetary magnetic field. However, the results of the GCM experiment are found to be somewhat limited by the ability of the model to successfully reproduce observed cloud cover. These results provide perhaps the most compelling evidence presented thus far of a GCR-climate relationship. From this analysis we conclude that a GCR-climate relationship is governed by both short-term GCR changes and internal atmospheric precursor conditions.
------------

Or take this study which highlights GCRs being a "plausable" Climate Driver:


http://cc.oulu.fi/~usoskin/personal/usoskin_CR_20 08.pdf


Quote:
In conclusion, a CR–climate link seems to be a
plausible climate driver, as supported by the bulk of
statistical studies and existing theoretical models.
----------



Low Level Cloud Cover and GCRs for Europe as presented by Usoskin et. al 2008.


Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting Snowlover123:


Hello TomTaylor,

I haven't debated you with this issue in quite a bit of a while :)

There is definite uncertainty regarding the feedbacks surrounding a doubling of CO2, but I have changed by stance slightly since we last debated.

There are negative feedbacks that exist within Earth's Climate, but they are not enough to cancel the effect that CO2 has. They significantly reduce the effect, however.

What you boxed was land use albedo changes. I am refering to the CLOUD albedo changes, which have added 7 w/m^2 to Earth's Energy Budget.

The IPCC does not list the change in the Cloud Forcing as a radiative forcing under the natural section, because they think Clouds can only change if temperature goes up or down, because clouds have been decreasing while temperature has gone up.

I can understand them not listing Cloud Cover as a forcing because there is still much uncertainty that surrounds it, but saying it's a feedback because it has been decreasing while temperature has gone up is sort of silly. It could easily be the other way around, and the radiative flux changes observed by CERES confirms this.
Yes it's been a while Snowlover.

I didn't box that, that was done from the site I found it off. Check the box two further down that lists cloud albedo changes.

Your entire argument (assuming all of the evidence and research findings are true, which I'm speculative of since most climate scientists have found that albedo changes in land (deforestation, raising albedo), ocean (melting ice, lowering albedo) and clouds (less clouds, lowering albedo) haven't changed temperatures much) just begs the question, what is causing the decrease in cloud cover? Aerosols, temperature, and humidity are the main factors affecting cloud formation. The only thing known to be consistently and currently influencing these factors over the last few decades is man. I suppose you could blame it on some sort of natural cycle, but there's no evidence for what this cycle is and it doesn't refute the idea that humans have altered the temperature and aerosol content of the atmosphere.
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362. j2008
Quoting NCHurricane2009:
Looks like the E-pac is getting attention....

Can someone answer if the disturbance in the Central Atlantic was Invest 90-L? I thought I saw it being declared yesterday afternoon...now its not declared as an Invest....

I highly doubt that it was labled, I dont think they have found a COC/LLC anywhere in the blob that is sustaining convection and is worthy of an invest lable. IMO it shouldnt be to much longer till we get one though.
Member Since: December 19, 2008 Posts: 1 Comments: 224

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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