Superstorm Sandy and the importance of polar orbiting satellites in forecasting

By: Dr. Jeff Masters , 8:19 PM GMT on January 03, 2013

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On the 23rd of October, the 18th named storm of the 2012 Atlantic hurricane season, Tropical Storm Sandy, was born in the Central Caribbean. As is common for late-season storms in the Caribbean, Sandy moved northwards across Cuba. The official forecasts from the National Hurricane Center issued on October 23 called for Sandy to turn to the northeast after crossing Cuba, and head into the Central Atlantic. This forecast was based on the output from five of our top six computer models, which all predicted that an upper-level low pressure system in the Central Atlantic would be strong enough to pull Sandy northeastwards. However, the global weather forecast model run by the European Center for Medium-Range Weather Forecasts (ECMWF) showed a disturbing possibility: the upper-level low pressure system in the Central Atlantic would not be strong enough to turn Sandy to the northeast. The hurricane would instead get caught up in the flow associated with a trough of low pressure approaching the U.S. East Coast, and Sandy would get slung into New York or New Jersey on October 29. While the ECMWF model was the best performing model for tracking Atlantic hurricanes in both 2010 and 2011, and had done very well again so far in 2012, the American GFS model had outperformed the ECMWF model several times during the 2012 season. NHC elected to discount the ECMWF forecast for Sandy as an outlier, and went with the forecast from the GFS and other models. By October 25, it was clear that the ECMWF model had the right idea all along. More models were now showing the turn towards New York, and the official NHC forecast now called for Sandy to make landfall in New York or New Jersey on October 29. The ECMWF model's early forecast of a track for Sandy into the Northeast was critical for allowing additional time for residents to prepare for arrival of the devastating storm. So what enabled the ECMWF model to make such an excellent forecast for Sandy, six days in advance?


Figure 1. This image uses the model output from the ECMWF experiment, showing where Sandy was predicted to be located five-days out with the normal satellite data inputs into the model (left) and without any polar-orbiting satellite data (right). Both position and intensity forecasts were affected--Sandy stays out to sea without the polar-orbiting satellite data, and the closer isobar lines encircling the storm also imply a more organized and stronger system. Image credit: NOAA.

Polar satellite data: a key to ECMWF model success
The ECWMF has a very sophisticated technique called "4-D Var" for gathering all the current weather data over the Earth and putting the data on a 3-dimensional grid that is then used as the initial "reality" of the current weather for the model to use for its forecast. The old expression, "garbage in, garbage out" is a truism for weather forecast models. If you don't properly characterize the initial state of the atmosphere, the errors you start off with will grow and give a lower-quality forecast. Data from geostationary satellites, which sit continuously at one spot above the globe, are easy to assimilate, and all the models use this data. However, the ECMWF model's superior technique used to assimilate the initial data allows inclusion of data from a large number of polar-orbiting satellites, which the other models cannot do as well. Polar-orbiting satellites orbit Earth at an altitude of 540 miles twice per day, circling from pole to pole. Their data is difficult to use, since the it is only available twice per day at each spot on the Earth, and the time of availability is different for each location. According to an email I received from Jean-Noël Thépaut, the chief of the Data Division of the Research Department at the European Center for Medium-Range Weather Forecasts, the ECMWF model uses data from at least fourteen polar orbiting satellites: N-15, N-19, N-19, N-17 (ozone SBUV instrument only), Metop-A, AQUA, NPP (ATMS instrument only), AURA (ozone OMI data only), F-17, TRMM (TMI data), COSMIC, GRACE-A, TERRASAR, and the GPSRO data on top of METOP-GRAS. The data of most importance is the data collected in the infrared and microwave wavelengths, as well as atmospheric density data obtained via GPS radio occultation (as a polar orbiting satellite goes over the horizon, the GPS signals from the satellite get bent by Earth's atmosphere, with the amount of bending proportional to the density of the atmosphere. This GPS Radio Occultation data is gathered from eight polar orbiting satellites, and fed into both the ECMWF and GFS models.) You can find a nice summary of the impacts of polar orbiting satellite data on weather prediction models at this link.)


Figure 2. Forecast track error for four of our top models used to predict Hurricane Sandy, for their runs that began at 00Z October 25, 2012. By this time, the GFDL model had joined the ECMWF in predicting that Sandy would make landfall in Southern New Jersey in five days. The GFS and HWRF models made good 1 - 3 day forecasts, but failed to anticipate Sandy's north-northwestward turn towards the U.S. coast. Image credit: Morris Bender, NOAA/GFDL.

As originally reported by the Washington Post's Capital Weather Gang, then confirmed in a NOAA press release, a study done by ECMWF research scientist Tony McNally found that if the ECMWF model did not have all of the data from the fourteen polar orbiting satellites, the five-day forecast of the model for Hurricane Sandy would have shown Sandy missing the Northeast U.S. This brings up a concern, since the U.S. polar orbiting satellite program is behind schedule. As explained by Andrew Freedman of Climate Central, the program is plagued by mismanagement, billions in cost overruns, and technical development challenges. The next polar orbiting satellite is not scheduled to be launched until 2017, and one or more of the existing polar orbiting satellites are expected to fail before then. This will result in a degradation of our ability to observe and predict the weather, and may result in poorer forecasts for storms like Hurricane Sandy. Given that the ECMWF model used data from fourteen polar orbiting satellites, the failure of just one satellite may not have made a significant difference in its forecast for Sandy. But if we lose several of these key satellites by 2017, our hurricane forecasts in 2017 may be worse than they were in 2012. To figure out how to cope with the loss of satellite-derived data, NOAA is conducting a Gap Risk Study that seeks ideas from researchers and the public on how NOAA can preserve the quality of its weather model forecasts in the event of the failure of one or more polar orbiting satellites in the coming years.


Figure 3. A tanker rests on the southern shore after being swept onto land by a storm surge due to Superstorm Sandy, Friday, Nov. 2, 2012, in the Staten Island borough of New York. (AP Photo/ John Minchillo)

Links
Eric Berger of the Houston Chronicle has an interview with Jean-Noël Thépaut, chief of the Data Division of the Research Department at the European Center for Medium-Range Weather Forecasts, on why the European model did so well with Hurricane Sandy.

Jeff Masters

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Quoting Tazmanian:
with the jet moveing well N next week and with the wind shear all ready runing way be low norml will need tooo keep a eye in the Caribbean has wind wind shear may be lowering there next week





are there any mode runs at all showing any thing fourming in the Caribbean with in the next week all so what do mode runs show for wind shear in the Caribbean they are runing way be low norml with the jet moveing way up N next week i think wind shear could go even lower opening a window for some in too fourm

Taz, it's January. Yes, wind shear is below average. But dry air is in abundance across the Caribbean and you need a catalyst for development...a tropical wave, stalled out front, etc. We don't have that. Don't expect anything to form for the next three months at least.
Member Since: July 6, 2010 Posts: 113 Comments: 32292
Quoting Tazmanian:
with the jet moveing well N next week and with the wind shear all ready runing way be low norml will need tooo keep a eye in the Caribbean has wind wind shear may be lowering there next week





are there any mode runs at all showing any thing fourming in the Caribbean with in the next week all so what do mode runs show for wind shear in the Caribbean they are runing way be low norml with the jet moveing way up N next week i think wind shear could go even lower opening a window for some in too fourm

No model shows anything developing into a tropical system. It is still January, there won't be any tropical development for at least a few more months.
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Member Since: July 21, 2011 Posts: 83 Comments: 7167
It's been raining here all day. Kinda hard to tell.

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744. Skyepony (Mod)
Better chance of a shallow warm core hitting Greenland next week.

Member Since: August 10, 2005 Posts: 175 Comments: 38218
743. VR46L
The invest to the north of Australia seems to be in a good environment for developement

Loop Embedded Of Water Vapour imagery From RAMMB


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Hope it falls where it will help...

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with the jet moveing well N next week and with the wind shear all ready runing way be low norml will need tooo keep a eye in the Caribbean has wind wind shear may be lowering there next week





are there any mode runs at all showing any thing fourming in the Caribbean with in the next week all so what do mode runs show for wind shear in the Caribbean they are runing way be low norml with the jet moveing way up N next week i think wind shear could go even lower opening a window for some in too fourm
Member Since: May 21, 2006 Posts: 5091 Comments: 115244
593. Thecanadian 12:35 PM EST on January 05, 2013

Awesome, thank you for sharing that with us!

596. Neapolitan 12:42 PM EST on January 05, 2013

well said Nea


600. Skyepony 12:53 PM EST on January 05, 2013

You bring the most interesting things here.. thank you. So much nicer than trying to figure stuff like this out;
Post hoc multiple comparisons were made using Tukey’s Honestly Significant Difference test. Linear regression and ANOVA were used to test for significance of fecal and total coliform data vs. salinity. For all analyses, differences were considered significant at p # 0.05.

Dime will get you a dollar RTS understands it.

Largo... I blame this miserable cold drizzle we are having on you. We were fine until you complained about it this morning and shooed it this way :(.

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Link posted this earlier but i thought it was very cool so here it is again this is a snow squall that rolled through my town in southern new brunswick i filmed this out my back window . u can see the hill dissapear and it takes about one minute for it to hit me the wind shot up to 80 km hour with whiteout conditions for 5 minutes ! very cool to see first hand
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Member Since: July 21, 2011 Posts: 83 Comments: 7167
Sonamu remains a sheared cyclone:

Member Since: July 21, 2011 Posts: 83 Comments: 7167
736. Skyepony (Mod)
Quoting Xandra:

The same video was published on Aug 31, 2012:

STRANGE LIGHT AND ORBS - Brazil - 15 MAY 2011 19.50




That's before Sandy even. The other looked like Sandy with the Empire State Building & the wild dancing trees, but I had my doubts about this one..looks like some storm though. Under the car lights the road reflects them like it's wet. Sounds like wind & rain.
Member Since: August 10, 2005 Posts: 175 Comments: 38218
Poor almost snow-less Chicago, 0.4" for one day for the entire year is pretty sad.

@NWSChicago

MT @everythingwx: The 0.4" of snow (as of 4pm) Chicago-O'Hare made this the snowiest day in #Chicago so far this winter. #ILwx
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Music to my ears, in a severe drought and there is a 90 percent chance of rain and thunderstorms here Tuesday. :)
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Quoting JustPlantIt:
Yes, I am trying to verify it... just get lots of criticism for it. Guess looking at something odd is not allowed on this site. Seeing something that does not make sense does not mean that I am wrong or that you are right. Glad that Columbus thought that the earth was round and not flat. Guess what, I think outside of your boxes and try to keep a clear and open mind to what I DO NOT KNOW; to find the answers... no matter how idiotic. I would say that I am In great company with this venue.


No. It's not like that at all. No one is telling you to "not look at something odd." And this has nothing to do with Columbus, or Galileo, or whatever other allegory you'd like to use. Just because you've discovered the internet does not mean you've figured out something new or that you are going to be the next amazing thing. That takes critical thinking skills.

Perhaps, in the future, when you see something on the internet that seems "odd" or that you'd like to "keep verifying," it might be suggested that you do a few searches first, or read up on the topic. If it still seems like the video is A) in a place similar to its description and B) of a phenomena that has actually been documented before, then maybe post it with something to the effect of "this video claims to be of lights about the time of the earthquake, but I don't know about that."

No reason to lash out at people... that's why you are going to be criticized. Just learn from it, improve your critical thinking skills, and move on.
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Quoting TropicalAnalystwx13:

Nobody is criticizing you, chill out.
CHILLIN... thanks
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Quoting JustPlantIt:
Yes, I am trying to verify it... just get lots of criticism for it. Guess looking at something odd is not allowed on this site. Seeing something that does not make sense does not mean that I am wrong or that you are right. Glad that Columbus thought that the earth was round and not flat. Guess what, I think outside of your boxes and try to keep a clear and open mind to what I DO NOT KNOW; to find the answers... no matter how idiotic. I would say that I am In great company with this venue.


Nobody is criticizing you, chill out.
Member Since: July 6, 2010 Posts: 113 Comments: 32292
Yes, I am trying to verify it... just get lots of criticism for it. Guess looking at something odd is not allowed on this site. Seeing something that does not make sense does not mean that I am wrong or that you are right. Glad that Columbus thought that the earth was round and not flat. Guess what, I think outside of your boxes and try to keep a clear and open mind to what I DO NOT KNOW; to find the answers... no matter how idiotic. I would say that I am In great company with this venue.
Quoting ScottLincoln:
Are people still seriously considering those videos going around the internet as possible "earthquake lights" sightings in Alaska? It looks very very similar to videos of the explosion in NYC during Hurricane Sandy, and the scenery in the videos looks nothing quite like what you'd find in Juneau or Anchorage.

I know it's hard to believe, but there are people out there in this world that use the anonymity and free speech ease of the internet to take credit for things that are not theirs, spread rumors that are not true, and basically just make crap up. Take a step back, have some skepticism, verify that it makes sense.

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Quoting allancalderini:
Oh my gosh until today I found that the 1938 hurricane season has a hurricane in the month of January.


According to the Atlantic hurricane best track, it is one of the five known Atlantic cyclones to occur in the month of January. The others being a system in 1951, which was recently reanalyzed; Hurricane Alice in 1955, a subtropical storm in 1978, and Tropical Storm Zeta in January of 2006.
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728. VR46L
Re Alaska lights ~Seems like an internet hoax to me LOL
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Quoting 636. Skyepony

The same video was published on Aug 31, 2012:

STRANGE LIGHT AND ORBS - Brazil - 15 MAY 2011 19.50


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Are people still seriously considering those videos going around the internet as possible "earthquake lights" sightings in Alaska? It looks very very similar to videos of the explosion in NYC during Hurricane Sandy, and the scenery in the videos looks nothing quite like what you'd find in Juneau or Anchorage.

I know it's hard to believe, but there are people out there in this world that use the anonymity and free speech ease of the internet to take credit for things that are not theirs, spread rumors that are not true, and basically just make crap up. Take a step back, have some skepticism, verify that it makes sense.
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Oh my gosh until today I found that the 1938 hurricane season has a hurricane in the month of January.
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The video is real, that's not the question, it's just NOT Juneau! Go to google images and check out Juneau. Gosh, some people are so stubborn, just won't admit when they are wrong.
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723. VR46L
Sonamu Pacific Funktop

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722. VR46L
4 invests and a cyclone in the indian ocean and the west Pacific

Current probability



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Quoting JustPlantIt:
NOT DONE HERE: Empire state building.... you've got to be kidding... Did anyone actually satelite this? REALLY those two buildings... World Trade Center... they are gone. Video as far as I am concerned IS REAL. Drop your drawers and get real. About an earthquake which is as much about weather as you can get. AND YES, know about the lightening that can occur with these or apparently is rare. NOT, it is real! Does anyone have any knowledge other than liking to talk just for a +. I am looking for real answers.

What does the World Trade Center have to do with the Empire State Building? They're two separate things.
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@NWSChicago
0.4" in #Chicago as of 4pm. Today likely is the 316th straight day w/out a 1" snow. The 319 day record, ending 1/6/1940, is likely to fall.
Member Since: July 6, 2010 Posts: 113 Comments: 32292
Member Since: July 21, 2011 Posts: 83 Comments: 7167
Yes... no rain or snow in that video either.
Quoting PlazaRed:

Heres the comment:-
694. WeatherNerdPR
The photos shows a small area of low lying buildings, probably typical of the city.
Also comments by people about the weather at the time were that it was fine, no rain and if there had been any it would have been snow.

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Quoting Levi32:
GEM ensembles say the area north of Darwin may stay tropically active even after the currently developing storm is gone.

Day 8 Precipitation:



It is the monsoon season down under.
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NOT DONE HERE: Empire state building.... you've got to be kidding... Did anyone actually satelite this? REALLY those two buildings... World Trade Center... they are gone. Video as far as I am concerned IS REAL. Drop your drawers and get real. About an earthquake which is as much about weather as you can get. AND YES, know about the lightening that can occur with these or apparently is rare. NOT, it is real! Does anyone have any knowledge other than liking to talk just for a +. I am looking for real answers.
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GEM ensembles say the area north of Darwin may stay tropically active even after the currently developing storm is gone.

Day 8 Precipitation:

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Published on Jan 5, 2013

In Australia, bushfires are destroying homes in the South East. Bush-fires are sweeping across the states of South Australia and Victoria. But the island state of Tasmania has been worst-Hit with the Fires being the most devastating in 50 years.

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Quoting JustPlantIt:
Where are those pictures?


Heres the comment:-
694. WeatherNerdPR
The photos shows a small area of low lying buildings, probably typical of the city.
Also comments by people about the weather at the time were that it was fine, no rain and if there had been any it would have been snow.
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Tasmania Fire Service

Current Bushfires & Other Incidents

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Thousands Flee Wildfires in Southern Australia

VOA News
January 05, 2013


Australian authorities say thousands of people have fled wildfires raging through southern Australia, with one blaze destroying dozens of homes in the southern island state of Tasmania.

The fires flared on Friday amid a record summer heat wave that pushed temperatures above 40 degrees Celsius in Tasmania, which is normally known for its cooler climate.

Tasmania police estimate that as of late Saturday, at least 70 percent of the buildings in and around the small community of Dunalley, about 55 kilometers east of the state capital, Hobart, had been destroyed.

Officials are investigating a report that one person has died in the blaze, but police say that so far no deaths have been confirmed.

Wildfires are common during the Australian summer. In February of 2009, hundreds of fires across Victoria state killed 173 people.

Watch related video of Australian wildfires


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Where are those pictures?
Quoting PlazaRed:
Finally!Photos.
Thank you,
Now that does not look anything like the videos.

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Quoting WeatherNerdPR:
Juneau, Alaska.

It doesn't look anything like the first video that was posted here.
Finally!Photos.
Thank you,
Now that does not look anything like the videos.
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Member Since: July 21, 2011 Posts: 83 Comments: 7167
706. Skyepony (Mod)
Quoting WeatherNerdPR:

If anything it would've been snowing in Juneau, since the temperature was probably well below freezing at the time the earthquake occurred(just before midnight).


Good point..It's been hovering around freezing. I thought it looked kind of flat but a nearby stations confers.
Member Since: August 10, 2005 Posts: 175 Comments: 38218
Quoting TomTaylor:
Seriously lol. People keep pointing out the forecasted tank in the NAO, particularly around the 12th through the 17th. Well guess what? Forcing from the Pacific (PDO influence, possible MJO contributions as well) is favoring a ridge along the SE US, and the result is warmth in the East despite a very low NAO.

12z GEFS NAO



12z GEFS 2m Temp Anomaly from the 12th to the 17th




Cold may very well still invade the East in the last third of January, but for now, the next week and a half are looking pretty nice for the East.

Well, looking pretty nice in the East unless you are snow lover :P
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Sometimes Ignorance is bliss... just copied a saying. What we don't know... might not hurt us; or if we did, we might be able to stop it.
Night all.
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Quoting Patrap:
Any usage of the Saffir-Simpson Scale in Overall impact is a poor way to relate the actual impact.

Ike, Rita, Katrina,Isaac and Sandy all have shown that a new way to relate Potential Impact to the Public is badly needed.


This iz the opinion of the poster.


Agree.

Keep the SS code, but add "Destructive Potential" from 1 to 5, for specific areas.
So Sandy could have read " Cat 2, DP 4 (or 5 or whatever the destructive potential is deemed to be) for areas in the direct path.
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Quoting Levi32:
I think when I get my model page up I'm going to just skip over the NAO graphics altogether. It's becoming way too much of a theme song for forecasters and weather nerds over the last two winters lol.
Seriously lol. People keep pointing out the forecasted tank in the NAO, particularly around the 12th through the 17th, alluding to the potential cold. Well guess what? Forcing from the Pacific (PDO influence, possible MJO contributions as well) is favoring a ridge along the SE US, and the result is warmth in the East despite a very negative NAO.

12z GEFS NAO



12z GEFS 2m Temp Anomaly from the 12th to the 17th




Cold may very well still invade the East in the last third of January, but for now, the next week and a half are looking pretty nice for the East.
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Quoting JustPlantIt:
I'm out on a limb. THAT VIDEO is NOT a mumble jumble of transformers. I've seen enough video of tornadoes and transformers burning. They do NOT light up the sky like this video... nor does a natural gas explosion. Yes, this is a weather extreme due to earthquake or something else.... not sure, but I'd like to find out the truth! Don't think it is available to normal people with half a brain.. or with a whole... NO NOT A HOLE but the whole.

Actually, looking at videos of power flashes they do light up the sky like that. After the flashes it is then obvious that power was knocked out in some of those areas.
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I'm out on a limb. THAT VIDEO is NOT a mumble jumble of transformers. I've seen enough video of tornadoes and transformers burning. They do NOT light up the sky like this video... nor does a natural gas explosion. Yes, this is a weather extreme due to earthquake or something else.... not sure, but I'd like to find out the truth! Don't think it is available to normal people with half a brain.. or with a whole... NO NOT A HOLE but the whole.
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Quoting Skyepony:


That's what I thought.. The first video it's obviously raining (sounds windy too)..Didn't rain in Juneau today either.

If anything it would've been snowing in Juneau, since the temperature was probably well below freezing at the time the earthquake occurred(just before midnight).
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Any usage of the Saffir-Simpson Scale in Overall impact is a poor way to relate the actual impact.

Ike, Rita, Katrina,Isaac and Sandy all have shown that a new way to relate Potential Impact to the Public is badly needed.


This iz the opinion of the poster.

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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.