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looking down for a living: how & why would you map snow depth on top of seaice?
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MrPosti...@kymhorsell.com
May 26, 2020, 9:25:37 PM5/26/20
to
Mapping Snow on Arctic Sea Ice
Kathryn Hansen & Kate Ramsayer
NASA Earth Observatory
Oct 2018 - April 2019
<https://eoimages.gsfc.nasa.gov/images/imagerecords/146000/146758/arctic_ice2_201904.jpg>
(NASA Earth Observatory images by Joshua Stevens, using data courtesy
of Kwok, R., et al. 2020).
For the past 2 decades, satellites and scientists have revealed an
ongoing, decades-long decline in Arctic sea ice, with implications for
global ecosystems, weather, and climate. Satellites are now tracking
what's happening to the reflective, insulating layer of snow atop the ice.
The snow layer is an important component of the sea ice system,
affecting how the ice grows and melts. In winter, blanket-like snow
cover insulates sea ice from frigid polar air, slowing ice growth. In
spring, snow cover must melt away before the ice surface can begin to
melt. By summer, melt water from the snow collects in ponds atop the
ice; this water absorbs heat from the Sun and can accelerate the
warming and melting of the ice.
Over the years, scientists have collected ground and airborne surveys
of snow depth here and there. But they need routine, widespread
measurements to detect the detailed variations in snow depth across
the ice cap and how it changes during the year. Those details are now
measurable, as scientists have created the first satellite-based maps
of snow accumulation on Arctic sea ice.
"This is the first time ever that we can get snow depth across the
entire Arctic Ocean's sea ice cover," said Ron Kwok, a sea ice
scientist at NASA's Jet Propulsion Laboratory and author of a
[29]study in JGR Oceans. "The Arctic region is a desert--but what snow
we do get is very important in terms of the climate and insulating sea ice."
The maps above show snow depths across Arctic sea ice, averaged
monthly from Oct 2018 through April 2019. Snow starts building up
slowly in Oct, when newly formed ice has an average of about 5
centimeters (2 inches) of snow on it and multiyear ice has an average
of 14 centimeters (5.5 inches). Snowfall picks up in Dec and
Jan and reaches its maximum depth in April, when the relatively
new ice has an average of 17 cm (6.7 in) of snow cover and the older
ice has an average of 27 cm (10.6 inches).
To produce the maps, scientists compared elevation measurements from
two satellites. NASA's [30]Ice, Cloud and land Elevation Satellite-2
(ICESat-2) carries a laser altimeter, which uses pulses of light to
precisely measure the height of the first substance it hits--whether
that's open water, bare sea ice, or snow that has accumulated on top
of the ice. The European Space Agency's CryoSat-2 satellite carries a
radar altimeter; in contrast to lidar, the radio waves of radar mostly
pass through snow and reflect off the top of the ice. By calculating
the difference between these 2 measurements, scientists can estimate
the depth of the snow layer on top.
"The method is certainly the best approach to-date," Kwok said. "With
ICESat-2 and CryoSat-2, we are able to obtain a time-variable estimate
of the snow depth from observations, without resorting to models."
With additional years of observations, maps like these could help
scientists assess how climate change affects precipitation and the
accumulation of snow. The challenge, Kwok notes, is that the
measurement relies on having both satellites in orbit at the same
time. ICESat-2 is newer, having launched in 2018, while CryoSat-2 has
already been in orbit for a decade.
"If we lose CryoSat-2, then we are back to doing this with ICESat-2
alone," Kwok said. "The hope is that we'll be able to have a least a
few years to make progress toward improving models."
First-of-a-kind maps show how the depth of this insulating snow layer
changes from month to month.
Image of the Day for May 27, 2020
Instrument:
ICESat-2 -- ATLAS
References & Resources
* Kwok, R. et al. (2020) Arctic Snow Depth and Sea Ice Thickness From
ICESat-2 and CryoSat-2 Freeboards: A First Examination. JGR Oceans
125 (3), e2019JC016008. <https://doi.org/10.1029/2019JC016008>
* NASA Features (2020, May 14) NASAs ICESat-2 Measures Arctic Oceans
Sea Ice Thickness, Snow Cover.
<https://www.nasa.gov/feature/goddard/2020/icesat-2-measures-arctic-sea-ice-thickness-snow-cover>
* NASA Missions (2020) ICESat-2.
<https://www.nasa.gov/content/goddard/icesat-2>
--
Upcoming events:
08 Jun 2020 May US Release NOAA SOTC
08 Jul 2020 2020Q2 Billion Dollar Disasters NOAA
A man may fail many times but he isn't a failure until he begins to blame
someone else.
-- J. Paul Getty, 29 Aug 2017
[Literally!]
Peter Gleick @PeterGleick 26 May 2020 03:13Z
"Eat, drink, and be merry, for tomorrow we die" says the Bible but with
the pandemic and people ignoring expert medical advice it's getting a
bit too literal.
[Ratings!]
Dana Nuccitelli @dana1981 25 May 2020 22:54Z
23/50 state governors have >=70% #coronavirus response approval ratings.
42/50 have >=60% approval ratings.
49/50 have >=54% approval ratings.
@BrianKempGA and @realDonaldTrump have 43% approval ratings. Ouch.
<https://t.co/Ts9PpFO2Zf>washingtonpost.com/politics/2020/...
On a day of 'terrifying' 5-metre waves, one ride in Newcastle still has
people talking
ABC Newcastle, 26 May 2020 20:18Z
Last Sat is now known around Newcastle as 'Big Sat', and for one
local surfer "nothing comes close" to the wave he caught in front of a
packed beach of spectators.
Paul Graham @paulg 26 May 2020 20:23Z
They say pilots are the most dangerous when they have about 200 hours.
They have just enough experience to feel like they know what they're
doing, without actually knowing what they're doing. We're at that stage
with the coronavirus.
Porter Anderson @Porter_Anderson 26 May 2020 20:06Z
Media: @Worldometers' metrics -- one source used by @JHSPH_CHS
-- now shows the United States with 100,269 American deaths confirmed
in the #coronavirus #COVID19 pandemic. @JohnsHopkins'
dashboard has 98,636 (Worldometers traditionally is ahead)
<https://t.co/X8CNKlQbuO>worldometers.info/coronavirus/
[Fact-checking as "interference":]
Trump accuses Twitter of interfering in 2020 presidential election after
fact-check warning
ABC News, 27 May 2020 0:30Z
US President Donald Trump accuses Twitter of "completely stifling free
speech" after the social media company flagged some of his tweets with a
fact-check warning.
[Pandemics On Increase:]
Assaad Razzouk @AssaadRazzouk 26 May 2020 13:05Z
>Pandemics in last 102 years same as previous 2,000
>50% of outbreaks since 1900 in past 20 years
Why? Earth not coping with its worst infestation: Us
We're running out of time and can't afford not to apply lessons from
#coronavirus to #climate fight
<https://t.co/HrzCIaqxZa>scotsman.com/news/opinion/c...
pic.twitter.com/gW0DXYDrfe
AerosolWatch @AerosolWatch 26 May 2020 15:13Z
Intense #fires in Central America continue. 1-hr composite aerosol
optical depth (#AOD) from #GOES16 #ABI, 13:30-14:30 UTC
today, shows thick #smoke (maroon/purple/pink shading) located from
southern Mexico to TX, and across the Yucatan Peninsula and Gulf of
Mexico to Cuba. pic.twitter.com/voPvqRWEtN
[Warm Alaska:]
Brian Brettschneider @Climatologist49 26 May 2020 16:08Z
A 70°F Watch in now in effect for Anchorage. The first 70°F day of the
year is typically in the first week of June. #NotARealWatch
pic.twitter.com/2UDIAtaTCN
[Not If:]
Climate Signals @ClimateSignals 26 May 2020 16:07Z
According to a new study, it's not a question of if but when Louisiana
wetlands will vanish due to sea level rise. Sea level rise driven by
#climatechange is increasing inland flooding and the risk of
coastline erosion. <https://t.co/c0oYOFHX1y>bit.ly/2Ac38Va via @NOLAnews
pic.twitter.com/q2xZpMIamN
Capital Weather Gang @capitalweather 26 May 2020 18:06Z
A remarkable rain event in South Florida..., which is now shifting
toward the coastal Carolinas. Lots of flooding in Miami over the
holiday weekend (7.27" in 48 hours). <https://t.co/8UtsCRtjlQ>wapo.st/2zwzOsF
["Natural Cycle":]
Hunter Cutting @HunterCutting 26 May 2020 19:12Z
Gerry Bell, the forecast lead for the @NHC_Atlantic has now issued
a statement directly contradicting NOAA on the #climatechange link,
attributing the trend instead to the AMO as a "natural cycle" and
stating point blank: "This is not a global warming signal."
<https://t.co/HIMAGDX45B>twitter.com/MichaelEMann/s...
Michael E. Mann @MichaelEMann 26 May 2020 19:12Z
Replying to @HunterCutting @NHC_Atlantic @NOAA
Disconcerting that @NOAA @NHC_Atlantic is promoting climate
change denialism. The peer-reviewed literature now decisively refutes
such claims. See here and the references to the literature therein:
<https://t.co/X4B87I4F4z>nature.com/articles/s4146...
Bloomberg Green @climate 26 May 2020 20:17Z
German govt may not meet its legal obligations to cut air
pollution, so 2 environmental charities are suing <https://t.co/1illlXRxFZ>tri
b.al/TOiS7DC
[Data!]
KenCaldeira @KenCaldeira 26 May 2020 20:10Z
"Developing reliable hourly electricity demand data through screening
and imputation" @thruggles, @farnham_h2o and @DanTong12
have cleaned up EIA hourly electricity demand data for balancing
authorities in the contiguous United States. open source+data
<https://t.co/nmio3tWhaz>nature.com/articles/s4159...
KenCaldeira @KenCaldeira 26 May 2020 20:10Z
Replying to @KenCaldeira
If you are working with EIA electricity demand data, please consider
taking advantage of this cleaned-up data set. We are intending to make
this an ongoing community service, but in any case, all of the data and
processing is publicly available. pic.twitter.com/CjVWBY4Yqp
Climate Change International Media Newshub @GNewshub 26 May 2020 20:44Z
Mon, May 25th 2020, 8:00 pm - The abnormally warm temperatures in
Siberia have had impacts on sea ice in the Arctic Ocean and global
temperature anomalies. <https://t.co/FgX1ydQhvw>theweathernetwork.com/ca/news/articl...
Dana Nuccitelli @dana1981 26 May 2020 20:37Z
The highest per capita mortality in the world right now is Belgium at
0.08% of the population, which in the US would correspond to 268,000
deaths. But yeah, the Trump bar is so low that less than 8x worse than
the worst result in the world is a sign of success
<https://t.co/myQsJEtbCK>twitter.com/atrupar/status...
[LPA:]
The Weather Channel @weatherchannel 26 May 2020 19:12Z
NEW: The NHC has just designated the area of tropical disturbance off
of Florida as Invest 91L. We have the latest updates on the effects
LIVE on The Weather Channel. pic.twitter.com/VukLjJAsSN
National Hurricane Center @NHC_Atlantic 26 May 2020 21:0Z
An area of low pressure near the northeast Florida coast has a 30%
chance of becoming a tropical depression before it moves inland over
the southeast US by Wed. afternoon. Heavy rains and rough marine
conditions are likely even if it does not develop. <https://t.co/tW4KeFW0gB>hurricanes.gov
pic.twitter.com/m8rt5uFTil
AccuWeather @breakingweather 26 May 2020 20:06Z
.@AccuRayno explains what factors could inhibit further development
of a tropical system that has been soaking Florida. <https://t.co/AMp4UBdizg>bit.ly/2ZCkKnR
Kathryn Hansen & Kate Ramsayer
NASA Earth Observatory
Oct 2018 - April 2019
<https://eoimages.gsfc.nasa.gov/images/imagerecords/146000/146758/arctic_ice2_201904.jpg>
(NASA Earth Observatory images by Joshua Stevens, using data courtesy
of Kwok, R., et al. 2020).
For the past 2 decades, satellites and scientists have revealed an
ongoing, decades-long decline in Arctic sea ice, with implications for
global ecosystems, weather, and climate. Satellites are now tracking
what's happening to the reflective, insulating layer of snow atop the ice.
The snow layer is an important component of the sea ice system,
affecting how the ice grows and melts. In winter, blanket-like snow
cover insulates sea ice from frigid polar air, slowing ice growth. In
spring, snow cover must melt away before the ice surface can begin to
melt. By summer, melt water from the snow collects in ponds atop the
ice; this water absorbs heat from the Sun and can accelerate the
warming and melting of the ice.
Over the years, scientists have collected ground and airborne surveys
of snow depth here and there. But they need routine, widespread
measurements to detect the detailed variations in snow depth across
the ice cap and how it changes during the year. Those details are now
measurable, as scientists have created the first satellite-based maps
of snow accumulation on Arctic sea ice.
"This is the first time ever that we can get snow depth across the
entire Arctic Ocean's sea ice cover," said Ron Kwok, a sea ice
scientist at NASA's Jet Propulsion Laboratory and author of a
[29]study in JGR Oceans. "The Arctic region is a desert--but what snow
we do get is very important in terms of the climate and insulating sea ice."
The maps above show snow depths across Arctic sea ice, averaged
monthly from Oct 2018 through April 2019. Snow starts building up
slowly in Oct, when newly formed ice has an average of about 5
centimeters (2 inches) of snow on it and multiyear ice has an average
of 14 centimeters (5.5 inches). Snowfall picks up in Dec and
Jan and reaches its maximum depth in April, when the relatively
new ice has an average of 17 cm (6.7 in) of snow cover and the older
ice has an average of 27 cm (10.6 inches).
To produce the maps, scientists compared elevation measurements from
two satellites. NASA's [30]Ice, Cloud and land Elevation Satellite-2
(ICESat-2) carries a laser altimeter, which uses pulses of light to
precisely measure the height of the first substance it hits--whether
that's open water, bare sea ice, or snow that has accumulated on top
of the ice. The European Space Agency's CryoSat-2 satellite carries a
radar altimeter; in contrast to lidar, the radio waves of radar mostly
pass through snow and reflect off the top of the ice. By calculating
the difference between these 2 measurements, scientists can estimate
the depth of the snow layer on top.
"The method is certainly the best approach to-date," Kwok said. "With
ICESat-2 and CryoSat-2, we are able to obtain a time-variable estimate
of the snow depth from observations, without resorting to models."
With additional years of observations, maps like these could help
scientists assess how climate change affects precipitation and the
accumulation of snow. The challenge, Kwok notes, is that the
measurement relies on having both satellites in orbit at the same
time. ICESat-2 is newer, having launched in 2018, while CryoSat-2 has
already been in orbit for a decade.
"If we lose CryoSat-2, then we are back to doing this with ICESat-2
alone," Kwok said. "The hope is that we'll be able to have a least a
few years to make progress toward improving models."
First-of-a-kind maps show how the depth of this insulating snow layer
changes from month to month.
Image of the Day for May 27, 2020
Instrument:
ICESat-2 -- ATLAS
References & Resources
* Kwok, R. et al. (2020) Arctic Snow Depth and Sea Ice Thickness From
ICESat-2 and CryoSat-2 Freeboards: A First Examination. JGR Oceans
125 (3), e2019JC016008. <https://doi.org/10.1029/2019JC016008>
* NASA Features (2020, May 14) NASAs ICESat-2 Measures Arctic Oceans
Sea Ice Thickness, Snow Cover.
<https://www.nasa.gov/feature/goddard/2020/icesat-2-measures-arctic-sea-ice-thickness-snow-cover>
* NASA Missions (2020) ICESat-2.
<https://www.nasa.gov/content/goddard/icesat-2>
--
Upcoming events:
08 Jun 2020 May US Release NOAA SOTC
08 Jul 2020 2020Q2 Billion Dollar Disasters NOAA
A man may fail many times but he isn't a failure until he begins to blame
someone else.
-- J. Paul Getty, 29 Aug 2017
[Literally!]
Peter Gleick @PeterGleick 26 May 2020 03:13Z
"Eat, drink, and be merry, for tomorrow we die" says the Bible but with
the pandemic and people ignoring expert medical advice it's getting a
bit too literal.
[Ratings!]
Dana Nuccitelli @dana1981 25 May 2020 22:54Z
23/50 state governors have >=70% #coronavirus response approval ratings.
42/50 have >=60% approval ratings.
49/50 have >=54% approval ratings.
@BrianKempGA and @realDonaldTrump have 43% approval ratings. Ouch.
<https://t.co/Ts9PpFO2Zf>washingtonpost.com/politics/2020/...
On a day of 'terrifying' 5-metre waves, one ride in Newcastle still has
people talking
ABC Newcastle, 26 May 2020 20:18Z
Last Sat is now known around Newcastle as 'Big Sat', and for one
local surfer "nothing comes close" to the wave he caught in front of a
packed beach of spectators.
Paul Graham @paulg 26 May 2020 20:23Z
They say pilots are the most dangerous when they have about 200 hours.
They have just enough experience to feel like they know what they're
doing, without actually knowing what they're doing. We're at that stage
with the coronavirus.
Porter Anderson @Porter_Anderson 26 May 2020 20:06Z
Media: @Worldometers' metrics -- one source used by @JHSPH_CHS
-- now shows the United States with 100,269 American deaths confirmed
in the #coronavirus #COVID19 pandemic. @JohnsHopkins'
dashboard has 98,636 (Worldometers traditionally is ahead)
<https://t.co/X8CNKlQbuO>worldometers.info/coronavirus/
[Fact-checking as "interference":]
Trump accuses Twitter of interfering in 2020 presidential election after
fact-check warning
ABC News, 27 May 2020 0:30Z
US President Donald Trump accuses Twitter of "completely stifling free
speech" after the social media company flagged some of his tweets with a
fact-check warning.
[Pandemics On Increase:]
Assaad Razzouk @AssaadRazzouk 26 May 2020 13:05Z
>Pandemics in last 102 years same as previous 2,000
>50% of outbreaks since 1900 in past 20 years
Why? Earth not coping with its worst infestation: Us
We're running out of time and can't afford not to apply lessons from
#coronavirus to #climate fight
<https://t.co/HrzCIaqxZa>scotsman.com/news/opinion/c...
pic.twitter.com/gW0DXYDrfe
AerosolWatch @AerosolWatch 26 May 2020 15:13Z
Intense #fires in Central America continue. 1-hr composite aerosol
optical depth (#AOD) from #GOES16 #ABI, 13:30-14:30 UTC
today, shows thick #smoke (maroon/purple/pink shading) located from
southern Mexico to TX, and across the Yucatan Peninsula and Gulf of
Mexico to Cuba. pic.twitter.com/voPvqRWEtN
[Warm Alaska:]
Brian Brettschneider @Climatologist49 26 May 2020 16:08Z
A 70°F Watch in now in effect for Anchorage. The first 70°F day of the
year is typically in the first week of June. #NotARealWatch
pic.twitter.com/2UDIAtaTCN
[Not If:]
Climate Signals @ClimateSignals 26 May 2020 16:07Z
According to a new study, it's not a question of if but when Louisiana
wetlands will vanish due to sea level rise. Sea level rise driven by
#climatechange is increasing inland flooding and the risk of
coastline erosion. <https://t.co/c0oYOFHX1y>bit.ly/2Ac38Va via @NOLAnews
pic.twitter.com/q2xZpMIamN
Capital Weather Gang @capitalweather 26 May 2020 18:06Z
A remarkable rain event in South Florida..., which is now shifting
toward the coastal Carolinas. Lots of flooding in Miami over the
holiday weekend (7.27" in 48 hours). <https://t.co/8UtsCRtjlQ>wapo.st/2zwzOsF
["Natural Cycle":]
Hunter Cutting @HunterCutting 26 May 2020 19:12Z
Gerry Bell, the forecast lead for the @NHC_Atlantic has now issued
a statement directly contradicting NOAA on the #climatechange link,
attributing the trend instead to the AMO as a "natural cycle" and
stating point blank: "This is not a global warming signal."
<https://t.co/HIMAGDX45B>twitter.com/MichaelEMann/s...
Michael E. Mann @MichaelEMann 26 May 2020 19:12Z
Replying to @HunterCutting @NHC_Atlantic @NOAA
Disconcerting that @NOAA @NHC_Atlantic is promoting climate
change denialism. The peer-reviewed literature now decisively refutes
such claims. See here and the references to the literature therein:
<https://t.co/X4B87I4F4z>nature.com/articles/s4146...
Bloomberg Green @climate 26 May 2020 20:17Z
German govt may not meet its legal obligations to cut air
pollution, so 2 environmental charities are suing <https://t.co/1illlXRxFZ>tri
b.al/TOiS7DC
[Data!]
KenCaldeira @KenCaldeira 26 May 2020 20:10Z
"Developing reliable hourly electricity demand data through screening
and imputation" @thruggles, @farnham_h2o and @DanTong12
have cleaned up EIA hourly electricity demand data for balancing
authorities in the contiguous United States. open source+data
<https://t.co/nmio3tWhaz>nature.com/articles/s4159...
KenCaldeira @KenCaldeira 26 May 2020 20:10Z
Replying to @KenCaldeira
If you are working with EIA electricity demand data, please consider
taking advantage of this cleaned-up data set. We are intending to make
this an ongoing community service, but in any case, all of the data and
processing is publicly available. pic.twitter.com/CjVWBY4Yqp
Climate Change International Media Newshub @GNewshub 26 May 2020 20:44Z
Mon, May 25th 2020, 8:00 pm - The abnormally warm temperatures in
Siberia have had impacts on sea ice in the Arctic Ocean and global
temperature anomalies. <https://t.co/FgX1ydQhvw>theweathernetwork.com/ca/news/articl...
Dana Nuccitelli @dana1981 26 May 2020 20:37Z
The highest per capita mortality in the world right now is Belgium at
0.08% of the population, which in the US would correspond to 268,000
deaths. But yeah, the Trump bar is so low that less than 8x worse than
the worst result in the world is a sign of success
<https://t.co/myQsJEtbCK>twitter.com/atrupar/status...
[LPA:]
The Weather Channel @weatherchannel 26 May 2020 19:12Z
NEW: The NHC has just designated the area of tropical disturbance off
of Florida as Invest 91L. We have the latest updates on the effects
LIVE on The Weather Channel. pic.twitter.com/VukLjJAsSN
National Hurricane Center @NHC_Atlantic 26 May 2020 21:0Z
An area of low pressure near the northeast Florida coast has a 30%
chance of becoming a tropical depression before it moves inland over
the southeast US by Wed. afternoon. Heavy rains and rough marine
conditions are likely even if it does not develop. <https://t.co/tW4KeFW0gB>hurricanes.gov
pic.twitter.com/m8rt5uFTil
AccuWeather @breakingweather 26 May 2020 20:06Z
.@AccuRayno explains what factors could inhibit further development
of a tropical system that has been soaking Florida. <https://t.co/AMp4UBdizg>bit.ly/2ZCkKnR
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