Record warmth at the top of the Greenland Ice Sheet

By: Dr. Jeff Masters , 9:25 PM GMT on July 18, 2012

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The coldest place in Greenland, and often the entire Northern Hemisphere, is commonly the Summit Station. Located at the top of the Greenland Ice Sheet, 10,551 feet (3216 meters) above sea level, and 415 miles (670 km) north of the Arctic Circle, Summit rarely sees temperatures that rise above the freezing mark. In the 12-year span 2000 - 2011, Summit temperatures rose above freezing only four times, according to weather records researcher Maximiliano Herrera. But remarkably, over the past week, temperatures at Summit have eclipsed the freezing mark on five days, including four days in a row from July 11 - 14. There are actually three weather stations located at the location--Summit, Summit-US, and Summit AWS. The highest reliable temperature measured at any of the three stations is now the 3.6°C (38.5°F) measured on Monday, July 16, 2012 at Summit-US. A 4.4°C reading at Summit in May, 2010 is bogus, as can be seen by looking at the adjacent station. Similarly, a 3.3°C reading from June 2004 is also bad. Records at Summit began in 1987.


Video 1. A 20-ton tractor attempting to repair a bridge washed out by the raging Watson River on July 11, 2012 in Kangerlussauaq, Greenland gets washed downstream. The driver escaped unharmed. Image taken from an article, Warm air over the ice sheet provides great drama in Greenland, at the Danish Meteorological Institute's web site.

Record heat leads to major flooding in Greenland
The record heat has triggered significant melting of Greenland's Ice Sheet. According to the Arctic Sea Ice Blog, on July 11, glacier melt water from the Russell Glacier flooded the Watson River, smashing two bridges connecting the north and south of Kangerlussuaq (Sønder Strømfjord), a small settlement in southwestern Greenland. The flow rate of 3.5 million liters/sec was almost double the previous record flow rate. The latest forecast for Summit calls for cooler conditions over the coming week, with no more above-freezing temperatures at Summit.

Another huge iceberg calves off of Greenland's Petermann Glacier
A massive ice island two times the size of Manhattan and half as thick as the Empire State Building calved off of Greenland's Petermann Glacier on Monday, July 16, 2012. According to Andreas Muenchow, associate professor of physical ocean science and engineering at the University of Delaware's College of Earth, Ocean, and Environment in his Icy Seas blog, the break-off point has been visible for at least 8 years in satellite imagery, and has been propagating at 1 km/year towards Nares Strait. The same glacier calved an iceberg twice as big back on August 4, 2010--the largest iceberg observed in the Arctic since 1962. The freshwater stored in that ice island could have kept the Delaware or Hudson rivers flowing for more than two years, or kept all U.S. public tap water flowing for 120 days. “While the size is not as spectacular as it was in 2010, the fact that it follows so closely to the 2010 event brings the glacier’s terminus to a location where it has not been for at least 150 years,” Muenchow said in a university press release. “Northwest Greenland and northeast Canada are warming more than five times faster than the rest of the world, but the observed warming is not proof that the diminishing ice shelf is caused by this, because air temperatures have little effect on this glacier; ocean temperatures do, and our ocean temperature time series are only five to eight years long — too short to establish a robust warming signal.”


Figure 1. The calving of a massive 46 square-mile iceberg two times the size of Manhattan from Greenland's Petermann Glacier on July 14 - 18, 2012, as seen using MODIS satellite imagery. Image credit: NASA.


Figure 2. Look familiar? Two years ago, a 100 square-mile ice island broke off the Petermann Glacier. It was the largest iceberg in the Arctic since 1962. Image taken by NASA's Aqua satellite on August 21, 2010. Image credit: NASA. I've constructed a 7-frame satellite animation available here that shows the calving and break-up of the Petermann Glacier ice island. The animation begins on August 5, 2010, and ends on September 21, with images spaced about 8 days apart. The images were taken by NASA's Aqua and Terra satellites.

Related posts

Unprecedented May heat in Greenland; update on 2011 Greenland ice melt

Greenland update for 2010: record melting and a massive calving event

Jeff Masters

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Quoting CaribBoy:


Could you please tell me what does that means?
Quoting CaribBoy:


Could you please tell me what does that means?


Sustained negative values of the SOI greater than −8 often indicate EL NINO

Sustainted positive values of the SOI greater than +8 are typical of a LA NINA

Member Since: June 20, 2012 Posts: 0 Comments: 2159
1279. nigel20
Quoting CaribBoy:


Could you please tell me what does that means?

The Southern Oscillation Index (SOI) is one measure of the large-scale fluctuations in air pressure occurring between the western and eastern tropical Pacific (i.e., the state of the Southern Oscillation) during El Niño and La Niña episodes. Traditionally, this index has been calculated based on the differences in air pressure anomaly between Tahiti and Darwin, Australia. In general, smoothed time series of the SOI correspond very well with changes in ocean temperatures across the eastern tropical Pacific. The negative phase of the SOI represents below-normal air pressure at Tahiti and above-normal air pressure at Darwin. Prolonged periods of negative SOI values coincide with abnormally warm ocean waters across the eastern tropical Pacific typical of El Niño episodes. Prolonged periods of positive SOI values coincide with abnormally cold ocean waters across the eastern tropical Pacific typical of La Niña episodes.

Link
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1278. EricSFL
Quoting CaribBoy:


I hate El Nino so this is great news. To me, El Nino means drought in the Eastern Caribbean (and probably elsewhere in the Caribbean)

... And a cooler, wetter Florida during winter which I actually prefer. It all depends where you are.
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Quoting CaribBoy:


Hey :) I'm in St Maarten!


The first time I went to St. Maarten (1984) We spent a week in Pelican Resort (Does not exists today). I was one of those fools who stood there near the fence of the airport and the beach, to watch a 747 departure...
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Quoting TropicalAnalystwx13:

El Nino is delayed.


Thanks
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Quoting wxmod:
Global pollution: ships, ships everywhere. Chug,chug,chug. The ocean is dying. Out of site, but not out of mind much longer. When the food is dead, you are hungry.





Those are chem trails
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Quoting nigel20:

Yeah, it was extremely dry here in Jamaica and across the most Caribbean during the 2009/2010 el nino.


..then from mid 2010 to early 2012 it turned wetter than average thanks to La Nina condition (in my area). I really hope for at least a normal rainfall pattern to resume for the coming month..
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1273. EstherD
Quoting akailm:
I would think anybody that would grow their food would consider what this says.. a real way to save h20, and a use for the so called carbon pollution,, it's real.. not bulimic.. a possible solution to the hysteria confronting us.examine if you can.. with a open mind.http://co2au.blogspot.com/2011/12/v-behavioru rldefaultvmlo_1587.html


First, here's a working link to the article.

Second, although I haven't read the entire thing word for word, I can make a few general comments on what I have read.

"We conclude plant physiology has never been properly understood or in the correct theoretical context. We have improved this understanding..."

Oh boy. Red Flag Warning... Whenever someone starts out by saying, in effect, all the accepted science in some well-studied field is dead wrong, you just know what's coming: Pseudoscience dead ahead!

And indeed we're not disappointed. The author proceeds to throw out just about everything that's known about plant physiology and biochemistry, and then to rewrite what's left to suit his own "theory".

If that weren't enough, the author then expounds on the quantum chemistry of carbon, but gets it mostly wrong. Apparently, he's never had a chemistry course where hybrid molecular orbitals and bonding theory were explained. And again, these misunderstandings are used to justify the author's particular point of view.

There's more, including mistaking correlation for causality when proposing a link between increasing CO2 concentration and higher agricultural productivity, but the above examples should suffice to give a feeling for the level of scientific understanding of the author.

So no, sorry, there's not much in that article worth examining in depth.

But since I'm likely to be accused of scientific closed-mindedness for saying that, I'll give the author one last shot...

"Science became a tool of government in the 19th century. It is largely sponsored by government and the victim of politics wherein the truth is what is said by powerful people. This has led science to make some huge blunders that it often ignores in passing."

Uhh huh...
-- EstherD
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Quoting CaribBoy:


Could you please tell me what does that means?

El Nino is delayed.
Member Since: July 6, 2010 Posts: 113 Comments: 31919
Quoting Tropicsweatherpr:
The 30 day SOI continues with the uptick,tonight up to -3.8,well above the -8 El Nino threshold.



Could you please tell me what does that means?
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1270. nigel20
Quoting CaribBoy:


I hate El Nino so this is great news. To me, El Nino means drought in the Eastern Caribbean (and probably elsewhere in the Caribbean)

Yeah, it was extremely dry here in Jamaica and across the most Caribbean during the 2009/2010 el nino.
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Quoting nigel20:

Hey CaribBoy! What island are you on?


Hey :) I'm in St Maarten!
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Quoting ProgressivePulse:
ECMWF is forecasting continued cooling in the EPAC, I'm really starting to doubt a bonified El Nino.





I hate El Nino so this is great news. To me, El Nino means drought in the Eastern Caribbean (and probably elsewhere in the Caribbean)
Member Since: Posts: Comments:
1267. bappit
1256. The GISS climate model can take dust into account (source), but it is a climate model. My guess for the operational global weather models is no. I have two reasons for this opinion.

1) The effects of dust are not all that well understood (previous source), so they would not know how to account for it in the model.

2) There would have to be some way of including data on the dust in the model input in a timely fashion. I don't think there is a good source of information on that. The SAL satellite images I see do not seem to discriminate on the basis of actual dust. I think they just see dry air since they will indicate a SAL where there is no dust source.

But that's just my guess. Maybe someone knows for sure.
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1266. nigel20
Quoting CaribBoy:


Good news, the N Islands still need good rainfall amount !! :)

Hey CaribBoy! What island are you on?
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This and about $4.00 bucks well get a nice coffee at Starbucks, but thanks Doc. Nice blog sir and keep up the good work. Cuz were all still standing here.
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Quoting Tropicsweatherpr:


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
946 PM AST THU JUL 19 2012

.UPDATE...SATELLITE DERIVED TPW ANALYSIS SUGGESTS ANOTHER BAND OF
DEEP MOISTURE JUST EAST OF THE LESSER ANTILLES. THIS BAND WILL
REACH THE USVI AND EASTERN PUERTO RICO BEFORE SUNRISE. AS A RESULT...
EXPECT ANOTHER ACTIVE DAY ON FRIDAY AS THIS MOIST AND UNSTABLE
AIR MASS MOVES ACROSS THE NORTHEASTERN CARIBBEAN. SEVERAL ROUNDS
OF SCATTERED TO NUMEROUS SHOWERS AND A COUPLE OF THUNDERSTORMS ARE
EXPECTED TO AFFECT PR AND USVI ON FRIDAY. MINOR CHANGES WERE DONE
TO THE FORECAST GRIDS THIS EVENING... MAINLY TO FINE TUNE THE
TIMING OF SHOWERS AND THUNDERSTORMS.


Good news, the N Islands still need good rainfall amount !! :)
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1263. nigel20
92W
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1261. Patrap
As the Warming increases the Global Water Vapor, we introduce more potential for Chaos as well.

And like CRS notes in the Loading the dice analogy,
well..it gloves nicely with the observations were seeing.
Member Since: July 3, 2005 Posts: 423 Comments: 127962


Radar picture from 9:36 CDT of storms rolling over my head. Lots of lightning but nothing serious. The wind wasn't even that bad even though NWS said 70mph.
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Quoting JeffMasters:


I'm pretty careful to say human-caused climate change increases the probability of certain extreme events. When discussing the crazy weather we've seen since 2010 in this post:

http://www.wunderground.com/blog/JeffMasters/comm ent.html?entrynum=2022

I said, "it strains the bounds of credulity that all of the extreme weather events--some of them 1-in-1000-year type events--could have occurred without a significant change to the base climate state."

Jeff Masters



This blog about "loading the dice" in terms of climate, helps me visualize the change...

http://tamino.wordpress.com/2012/07/20/craps/



One of the analogies sometimes used to explain the impact of global warming on the weather is that we're "loading the dice." Perhaps a better desrciption is that we're changing the dice.

...

And this illustrates one of the greatest potential dangers of global warming. If we increase the mean temperature (and we already have), of course we increase the likelihood of extreme heat waves (and we already have). But if, in addition, global warming increases the variance of regional temperatures, then we increase the likelihood of extreme heat waves by a lot. A helluva lot. The effect was profound when we only increased the standard deviation by a factor of 1.1 - what if it increases by a factor of 1.2 or even more? The increased likelihood of extreme heat would be astounding. What's more, we would also increase the likelihood of extreme cold spells!

In fact this applies to all weather phenomena, not just temperature. Climate change is likely to change the mean value of each, and increased variance will dramatically increase the likelihood of extremes, bringing more heat waves and cold spells, more flood and drought, etc. We may, in fact, already be witnessing exactly this phenomenon. Welcome to the rest of our lives.

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1257. Patrap




Global Climate Change Indicators
National Oceanic and Atmospheric Administration
National Climatic Data Center


Many lines of scientific evidence show the Earth's climate is changing.
This page presents the latest information from several independent measures of observed climate change that illustrate an overwhelmingly compelling story of a planet that is undergoing global warming.
It is worth noting that increasing global temperature is only one element of observed global climate change. Precipitation patterns are also changing; storms and other extremes are changing as well.

How do we know the Earth's climate is warming?

Thousands of land and ocean temperature measurements are recorded each day around the globe. This includes measurements from climate reference stations, weather stations, ships, buoys and autonomous gliders in the oceans. These surface measurements are also supplemented with satellite measurements. These measurements are processed, examined for random and systematic errors, and then finally combined to produce a time series of global average temperature change.
A number of agencies around the world have produced datasets of global-scale changes in surface temperature using different techniques to process the data and remove measurement errors that could lead to false interpretations of temperature trends. The warming trend that is apparent in all of the independent methods of calculating global temperature change is also confirmed by other independent observations, such as the melting of mountain glaciers on every continent, reductions in the extent of snow cover, earlier blooming of plants in spring, a shorter ice season on lakes and rivers, ocean heat content, reduced arctic sea ice, and rising sea levels.
Member Since: July 3, 2005 Posts: 423 Comments: 127962
This question i did in the afternoon can anybody respond?
The global models has the x factor of the SAL in his logic operation or only the dry air ?
Member Since: June 20, 2012 Posts: 0 Comments: 2159
Wow the Doc is on late tonight.
Member Since: August 14, 2010 Posts: 10 Comments: 16906
1254. bappit
Just use the steroid analogy in baseball. You know the overall increase is due to steroids but you don't know exactly which balls might have stayed in the park otherwise.
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1253. bappit
Here's another.

"African easterly waves have long been associated with the barotropic and baroclinic instability of the African easterly jet through meridional potential vorticity gradient reversals, which also may be achieved by concentrated convective heating of the ITCZ. A primary objective of this study is to explore whether African waves are initiated by the Charney-Stern instability in the region of reversed potential vorticity (PV) gradients, or whether convectively induced instability generates African waves, and the waves in turn enhance and organize the convection."

This one is from 2008 so it sounds like it is a bit complicated.
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1252. JeffMasters (Admin)
Quoting ScottLincoln:

Are you sure about that? I have a striking suspicion that at some point he probably said that.

Uh, yes it does matter. It matters very much so.


I'm pretty careful to say human-caused climate change increases the probability of certain extreme events. When discussing the crazy weather we've seen since 2010 in this post:

http://www.wunderground.com/blog/JeffMasters/comm ent.html?entrynum=2022

I said, "it strains the bounds of credulity that all of the extreme weather events--some of them 1-in-1000-year type events--could have occurred without a significant change to the base climate state."

Jeff Masters
Quoting TropicalAnalystwx13:
What's a good name for a facebook group for hurricanes?


GHB

GLOBAL
HURRICANE
BLOGERS
Member Since: June 20, 2012 Posts: 0 Comments: 2159
1250. wxmod
Quoting pottery:

Why is that ?
I have been trying to understand the mechanics of that.
Surely the waves are able to pick up more moisture over the sea than over the land?

So why do they fizzle over the ocean there ?


They suck up a bunch of sahara dust and that evens out the top to bottom temp of the clouds. No lapse rate equals no lift.
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Quoting stormchaser19:
July,19 2012


July, 19 2011

Either those two years are freakishly similar or you posted the same image twice.
Member Since: July 6, 2010 Posts: 113 Comments: 31919
Member Since: July 6, 2010 Posts: 113 Comments: 31919
1247. bappit
Quoting CaicosRetiredSailor:


In this paper

http://wind.mit.edu/~emanuel/tropical/Thorncroft_ Hodges.pdf


"Another growth region is located over northern Venezuela and Colombia, which also coincides with a genesis peak (cf. Fig. 5b). This is a region identi%uFB01ed by Molinari et al. (1997) as a potential vorticity sign reversal region. They suggested that AEWs could be reinvigorated there on their way into the eastern Paci%uFB01c."

Venuzuelan waves
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Quoting nigel20:


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
946 PM AST THU JUL 19 2012

.UPDATE...SATELLITE DERIVED TPW ANALYSIS SUGGESTS ANOTHER BAND OF
DEEP MOISTURE JUST EAST OF THE LESSER ANTILLES. THIS BAND WILL
REACH THE USVI AND EASTERN PUERTO RICO BEFORE SUNRISE. AS A RESULT...
EXPECT ANOTHER ACTIVE DAY ON FRIDAY AS THIS MOIST AND UNSTABLE
AIR MASS MOVES ACROSS THE NORTHEASTERN CARIBBEAN. SEVERAL ROUNDS
OF SCATTERED TO NUMEROUS SHOWERS AND A COUPLE OF THUNDERSTORMS ARE
EXPECTED TO AFFECT PR AND USVI ON FRIDAY. MINOR CHANGES WERE DONE
TO THE FORECAST GRIDS THIS EVENING... MAINLY TO FINE TUNE THE
TIMING OF SHOWERS AND THUNDERSTORMS.
Member Since: April 29, 2009 Posts: 75 Comments: 14229
Rain coming down really hard.Power went out for two minuets then turned back on.Whew.Storm is stil not over.Still bright flashes of lightning and loud thunder.Nature is sure putting on a show.
Member Since: August 14, 2010 Posts: 10 Comments: 16906
nvm
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1243. nigel20
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1242. wxmod
Global pollution: ships, ships everywhere. Chug,chug,chug. The ocean is dying. Out of site, but not out of mind much longer. When the food is dead, you are hungry.



Member Since: Posts: Comments:
We need to send some of this rain to the areas that need it!!!
Member Since: June 13, 2010 Posts: 0 Comments: 890
1240. pottery
Quoting Patrap:
I think of it like this,,even when one has a engine ready to go, say a one cylinder lawn mower. And all the numbers are right and the fuel s there, the spark, the air..and you pull the cord and nada.

But some engines, they fire bada boom, even though they old rusty, and not as perfect as the first.

Some sputter along till they find a better environment, some roll off with good mo and rotation.

Thats how I look at it in laymens terms Pottery




Great !
This I can comprendo !

Later. (or not, as the case may be)
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Quoting TheOnlyBravesFan:
Lightning is really close now, bright and strong..... Heavy downpours as well, flooding WILL be an issue
Yes this has to be some of the loudest thunder I've heard in my life time.
Member Since: August 14, 2010 Posts: 10 Comments: 16906
Quoting Patrap:
Weather456's Tropical Weather Blog
Tracking African Easterly Waves: Genesis


African Easterly Waves (AEWs) are warm season type disturbances, which are unique to the tropical North Atlantic Ocean. These disturbances form over Northern Africa and propagate westward at a mean speed of 15 knots. African easterly waves have wavelengths typical near 2500 km or 3-5 days. The Global Atmospheric Research Program (GARP) Atlantic Tropical Experiment (GATE) was conducted in 1974. Our understanding of the structure and dynamics of AEWs was enhanced by analyses using GATE observations. However, GATE experiments where located at the coast of Africa, when waves had already matured and exited the coast. Today, I am going to give a description of the genesis of AEWs using a collection of post-Gate researches, focusing on the one-month period between June 15-July 15 2008 and the two-week period between August 1-15 2007, as synoptic overviews, both periods of active wave development, which led to Hurricanes Bertha and Dean respectively.

Synoptic Overview of Western Africa

Before we continue, we have to understand the synoptic patterns over Northern Africa. The Northern section of Africa is described as having a desert climate of low precipitation and soil moisture and intense heating during the summer. As a result of intense heating, air rises in convection and forms a thermal low. This is the first feature we come across – The Saharan Thermal Low. Now this is not like any low-pressure system as it is very shallow, only extending to about 800 mb. Above the thermal low, air expands like an inflated balloon and cause pressure heights to shift upwards creating a high aloft. This is the second feature we will come across – the Saharan High.


I would like to see him back posting analysis of the waves.
Member Since: April 29, 2009 Posts: 75 Comments: 14229
1237. pottery
Posts 1231-1234.

Thanks. That should keep me quiet for a while!
A shame that, I know, but try to carry on without me.....

:):))
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1236. Patrap
I think of it like this,,even when one has a engine ready to go, say a one cylinder lawn mower. And all the numbers are right and the fuels there, the spark, the air..and you pull the cord and nada.

But some engines, they fire bada boom, even though they old rusty, and not as perfect as the first.

Some sputter along till they find a better environment, some roll off with good mo and rotation.

Thats how I look at it in laymens terms Pottery.







Member Since: July 3, 2005 Posts: 423 Comments: 127962
1235. nigel20
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1234. bappit
here's one

" it was Burpee (1972) who documented that the waves were being generated by an instability of the African easterly jet. (This instability - known as baroclinic-barotropic instability - is where the value of the potential vorticity begins to decrease toward the north.) The jet arises as a result of the reversed lower-tropospheric temperature gradient over western and central North Africa due to extremely warm temperatures over the Saharan Desert in contrast with substantially cooler temperatures along the Gulf of Guinea coast."

So when they lose the north-south temperature gradient found over land, they weaken. That's how I read it.
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Lightning is really close now, bright and strong..... Heavy downpours as well, flooding WILL be an issue
Member Since: Posts: Comments:
Quoting pottery:

Why is that ?
I have been trying to understand the mechanics of that.
Surely the waves are able to pick up more moisture over the sea than over the land?

So why do they fizzle over the ocean there ?



In this paper

http://wind.mit.edu/~emanuel/tropical/Thorncroft_ Hodges.pdf

in section 3. Growth and Decay rates

it mentions one explanation for the decay coming off the coast being due to the "relatively cool" SST there
Member Since: Posts: Comments:
1231. Patrap
Weather456's Tropical Weather Blog
Tracking African Easterly Waves: Genesis


African Easterly Waves (AEWs) are warm season type disturbances, which are unique to the tropical North Atlantic Ocean. These disturbances form over Northern Africa and propagate westward at a mean speed of 15 knots. African easterly waves have wavelengths typical near 2500 km or 3-5 days. The Global Atmospheric Research Program (GARP) Atlantic Tropical Experiment (GATE) was conducted in 1974. Our understanding of the structure and dynamics of AEWs was enhanced by analyses using GATE observations. However, GATE experiments where located at the coast of Africa, when waves had already matured and exited the coast. Today, I am going to give a description of the genesis of AEWs using a collection of post-Gate researches, focusing on the one-month period between June 15-July 15 2008 and the two-week period between August 1-15 2007, as synoptic overviews, both periods of active wave development, which led to Hurricanes Bertha and Dean respectively.

Synoptic Overview of Western Africa

Before we continue, we have to understand the synoptic patterns over Northern Africa. The Northern section of Africa is described as having a desert climate of low precipitation and soil moisture and intense heating during the summer. As a result of intense heating, air rises in convection and forms a thermal low. This is the first feature we come across – The Saharan Thermal Low. Now this is not like any low-pressure system as it is very shallow, only extending to about 800 mb. Above the thermal low, air expands like an inflated balloon and cause pressure heights to shift upwards creating a high aloft. This is the second feature we will come across – the Saharan High.
Member Since: July 3, 2005 Posts: 423 Comments: 127962
Great lightning show, up close to Howard U..... gusty winds and sheets of rain..... It smells like salt!!
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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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