Group for Earth Observation

No 71 - September 2021

Hurricane Ida, imaged by NASA’s Terra satellite at 21.21 UT on August 28, 2021 as it drenched the island of Cuba
Image: NASA Worldview Snapshots (https://wvs.earthdata.nasa.gov/)

Useful User Groups

GEO MANAGEMENT TEAM
General Information
John Tellick,email: information@geo-web.org.uk

GEO Newsletter Editor
Les Hamilton,

Weather Satellite Reports
This group provided weekly reports, updates and news
on the operational aspects of weather satellites.

https://groups.io/g/weather-satellite-reports

SatSignal
This end-user self help group is for users of David
Taylor’s Satellite Software Tools, including the orbit
predictor WXtrack, the file decoders GeoSatSignal and
SatSignal, the HRPT Reader program, the remapper
GroundMap, and the manager programs - MSG DataManager, GOES-ABI Manager, AVHRR Manager etc.

https://groups.io/g/SatSignal

email: geoeditor@geo-web.org.uk

Technical Consultant (Hardware)David Simmons
email: tech@geo-web.org.uk

Webmaster and Website Matters
Vacancy

MSG-1
This forum provides a dedicated area for sharing
information about hardware and software for receiving
and processing EUMETCast data.

https://groups.io/g/MSG-1
GEO-Subscribers
This is the official group is for subscribers of the Groupfor Earth Observation (GEO), aimed at enthusiasts
wishing to exchange information relating to either GEO
or Earth Observation satellites.

https://groups.io/g/GEO-Subscribers/

e-mail: webmaster@geo-web.org.uk

Management TeamDavid Anderson
Rob Denton
Nigel Evans: nigel.m0nde@gmail.com
Clive Finnis
Carol FinnisPeter GreenDavid SimmonsDavid Taylor
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Les HamiltonT

he recent IPCC (United Nations Intergovernmental Panel on Climate Change) CodeRed for Humanity warning has provided a serious wake-up call for us all: that thewarming of the planet is indeed the result of human activity and is in danger of gettingout of control.

If ever the reality of Climate Change were doubted, you just have to look at thissummer’s events around the world to change your mind! In Europe alone the monthof July was the hottest ever recorded, and temperatures climbing into the upper 40s
Celsius helped to spawn a rash of severe wildﬁres around the Mediterranean Sea:in Turkey, Greece, Italy, Spain and Algeria. In California, over a dozen major ﬁres
have destroyed vast areas of forest: the long lived Dixie ﬁre, which commenced on
July 13 and was still burning a month later, devastated over 2600 square kilometresand destroyed overt 1,000 structures, including hundreds of homes in Greenville,
California, and threatened to become the state’s worst ever. And across the world,the huge northeastern Russian republic of Yakutia has been declared a disaster area
with—at one point—over 150 wildﬁres burning simultaneously. There have also beenover 250 major ﬁres in the Amazon Basin this year. Some of the articles in this issue
relate directly to the above.

At the time of writing, there is still no word of a deﬁnite launch date for Russia’s longawaited Meteor M 2-3 satellite. The possible August launch date has now well andtruly lapsed. Perhaps there will be news of a launch before the end of this year. Fingers
crossed!

Contents
New aspect of Earth
Hurricane Ida devastates Louisiana
Sweet and Salty Sonora
Colour in the Northern Caspian Sea
NASA’s AIRS Tracks Record-Breaking Heat Wave
Sweden’s Siljan Ring
Frigid Weather in South Africa
A Summer of Fire-Breathing Smoke Storms
Malé, the MaldivesFire Island, Cabo Verde
Sentinel 2CHenri Soaks the Northeast
Smoke billows from fires in Turkey
California’s Dixie Fire Keeps on Growing
Annular Solar Eclipse
Add High Resolution Country Outlines with MeteorGIS
Violent Formation for Mistastin Lake
Summer Colour in Northern Seas
Satellite Status

European Space Agency
Les Hamilton
NASA Earth Observatory
MODIS WebJPL News
NASA Earth Observatory
MODIS Web Image of the Day
NASA Earth Observatory
European Space Agency
NASA Earth Observatory
Les Hamilton
NASA Earth Observatory
European Space Agency
NASA Earth Observatory
John Tellick
Les Hamilton
NASA Earth Observatory
NASA Earth Observatory

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New Aspect of Earth
European Space Agency

Credit: Contains modified Copernicus Sentinel data (2019–20), processed by ESA and cloud layer from NASA

This image of Earth was compiled using tens of thousands of images from theCopernicus Sentinel-2 mission. Thanks to the satellite era, we are better placed tounderstand the complexities of our planet, particularly with respect to global change.
Today’s satellites are used to answer important to understand how Earth works as asystem and how natural processes are changing under the pressure of human activity.
Satellites also provide essential information for everyday applications such as to improve
agricultural practices, for maritime safety and to help when natural disasters strike.

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Hurricane Ida Devastates Louisiana
Les Hamilton

Sixteen years to the very day—August 29—that
Hurricane Katrina hit Louisiana and Mississippi asa category-3 hurricane, Hurricane Ida made landfall
at Port Fourchon Louisiana with sustained winds of
240 kilometres per hour (kph) and a central pressureof 930 millibars. Whereas Katrina—which at one
point was a Category-5 hurricane—had weakened
to Category-3 when it struck, Category-4 Ida arrived
ashore at full power and weakened only slowly at
first, remaining a dangerous major hurricane forseveral hours thereafter.
In its day, Katrina was the fourth most powerfulhurricane to make landfall on the American
mainland: time will tell whether Ida has now
usurped this unwanted accolade.
The destructive power of a hurricane is generally
measured in the cost of the damage caused, andKatrina, primarily on account to the damage
resulting when the flood protection levees failed toprotect New Orleans, flooding 80% of the city forseveral weeks, tops the list. Happily, the re-enginered
levees around New Orleans kept the city safe frominundation by Ida, although the fierce winds andrain could not be prevented from severely damaging
property and wiping out power to over one million
consumers throughout the state of Louisiana.
In the final 24 hours prior to landfall, Ida underwent
what the National Hurricane Center termed a ‘rapid
intensification’. During this period, Ida’s centralpressure fell dramatically from 985 millibars (mB)
to 929 mB, with accompanying winds strengthening
from a mean of 150 kph to 270 kph. One factor
fuelling this rapid intensification was the unusuallywarm water in the Gulf of Mexico, between 30-31°C,
thus well above the 27°C threshold for hurricane
generation.

This TV screenshot shows a deserted street in storm ravaged
New Orleans where, thankfully, the levees held firm andwidescale inundation by floodwater was averted.

European Space Agency’s French astronaut Thomas Pesquet
photographed Hurricane Ida on August 29 during his mission
aboard the International Space Station.
Photo: ESA / NASAAt 2.50 am Central Daylight Time on August 30, the Visible
Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP
satellite acquired this night time view of Hurricane Ida.
Image: NASAIda first developed on the afternoon of August 26 as atropical depression southwest of Jamaica, and by thetime it made landfall on Cuba late the following day, hadintensified to Category-1 hurricane status, increasing tocategory-3 by the morning of August 29. In the west of
Cuba, winds of up to 114 kph toppled palm trees and many
houses were also destroyed by strong gusts. Electricity
supplies were cut in a number of locations.
After passing Cuba, Ida gained strength to became a
Category-4 hurricane, and when the storm first cameashore at Port Fourchon in Louisiana, an anemometerrecorded a wind gust of 277 kph. By the time Ida haddissipated two days later, the entire state of Louisianaand parts of neighbouring Mississippi were without power.
In all, some 1.3 million consumers were affected. And
as the situation was assessed, it became clear that thismajor power outage was going to last for many weeks:www.geo-web.org.uk

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In this TV image, a roof has collapsed in New Orleans

there would be no rapid return to normality, posing major
problems relating to air-conditioning and refrigerated
storage, particularly as daytime temperatures at this timeof the year frequently rise to 35°C and beyond. By theTuesday, hundreds of thousands of Louisianans weresweltering in the aftermath of Hurricane Ida, with neither
electricity or running water. People were clearing out foodrotting in refrigerators. Those with swimming pools sharedout buckets of water for bathing and to flush toilets.

Map plotting the track and the intensity of Ida, showing thelocation of the storm at 6-hour intervals.
Image: Wikimedia

The heavy rains that accompanied Hurricane Ida caused
widespread flooding, and in outer New Orleans, somepeople were forced to climb on to the roofs of theirhouses to escape floodwaters caused by the downpour.
In Mississippi, the rains caused a section of Highway 26
to collapse, seven vehicles tumbling into a deep hole, asa result of which two people lost their lives and ten others
suffered injuries.
Particularly hard hit were the coastal communities ofLouisiana, where roofs were ripped from homes, trees
were uprooted, cars overturned and power lines brought
down. Further damage was caused to many structures bywind borne debris,
Farther afield, Hurricane Ida curtailed almost the entire
Gulf Coast oil production, amounting to around 15% of
U.S. output. And as a precaution, Louisiana’s mainland
refineries were also shut down. This combination of factors
caused oil and gasoline prices to rise across the entire
United States.
With many transport links severed by downed power lines
and fallen trees, supplies of petrol were at a premium andlong queues formed at the few gas stations that had fuelleft and generator power to pump it.
With many water treatment plants becoming overwhelmedby floodwaters or crippled by power outages, some areas
suffered shortages of drinking water. Some four hundred
thousand inhabitants had no drinking water at all.
So serious was the situation in New Orleans, without
electricity, tap water and gasoline, that an evening curfew
was put in place to deter looters, while the thousands who
had evacuated the region prior to the storm were advised
not to return—there or anywhere else in south-east
Louisiana—until they were advised it was safe to do so.

This satellite image shows Hurricane Ida, southeast of the
Lousiana coast, on August 29 as a major Category-4 hurricane.
Image: NASAIn the immediate aftermath of Hurricane Ida’s assault on
Louisiana, it was estimated that the cost of repairing all thedamage to power lines, homes and infrastructure could be
fifteen billion dollars, though this may well prove to be anunderestimate. What is certain is that it will probably be
years rather than weeks or months before all the damage
can be made good and people’s lives return to normal.

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Sweet and Salty Sonora
NASA Earth Observatory
Story by Andrea Wenzel

This photo of the Sonoran Desert in Southern California
was taken with a camera mounted on the outside of theInternational Space Station. Blocky patches of farmland
are concentrated on both ends of the Salton Sea, anda short section of U.S Interstate 10—which stretches
over 3,800 kilometres from California to Florida—passes
through the flat areas between the mountains. An arrayof solar panels stands north of the interstate.
The nearby Orocopia and Chocolate Mountains arecomprised of a mix of sedimentary, igneous, andmetamorphic rocks along the San Andreas Fault,
allowing a variety of geologic features to be studied
within a short distance. The mountains were among
the locations that Apollo crews visited to train for theirtrips to the Moon. These ‘outdoor classrooms’ allowed
the astronauts to learn the skills necessary to makescientific observations in barren and challenging
landscapes. Such field work is still a part of astronauttraining.
The Salton Sea, California’s largest lake, started
growing in 1905 after an irrigation canal broke andallowed the Colorado River to fill the basin. This lakehas no natural outlet, so water must evaporate to leave
the system; this makes it saltier than the ocean. Water
continues to flow into the Salton Sea from agriculturalrunoff, but that runoff has decreased over time and does
not balance out the water lost to evaporation. Becauseof this, the lake is expected to become saltier with time.

This ISS External High-Definition Camera photograph ISS064-E-8944 was acquired on December 1, 2020,
with a Nikon D4 digital camera using a focal length of 85 millimeters. It is provided by the ISS Crew Earth
Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center.

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Colour in the Northern Caspian Sea
MODIS Web Image of the Day
https://modis.gsfc.nasa.gov/gallery/showall.php
Swirls of green and tan stained the northeastern
Caspian Sea on June 17, 2021, when theModerate Resolution Imaging Spectroradiometer(MODIS) on board NASA’s Terra satellite acquired
this true-colour image of the region.

carry sediment into the Sea, and their inflow
creates currents that can lift sediment from the
muddy bottom and carry it in swirls along withthe current. Heavy wind may also stir the shallow
waters and lift sediment.

The Caspian Sea is the world’s largest landlocked
body of water. Stretching 1,200 kilometres from
north to south, it intersects five countries in Asia
and Europe, with Kazakhstan wrapped aroundthe northeastern corner of this large landlocked
lake. While the water is deep in the southern andcentral portions of the Caspian Sea, the northern
section overlies a shelf, making it very shallow.
The north receives heavy freshwater inflow fromthe large Volga River and from the Ural River.
The Ural can be seen at the top of this image,but the Volga sits to the west (left). Both rivers

Sediment appears tan or mud-coloured where it
floats close to the surface, as can be seen along
the coastline. As sediment sinks, its reflectivity
changes, and this causes it to appear green intrue-colour MODIS images.
While most of the colour in the northeastern
Caspian Sea is probably sediment, it’s not possible
to rule out the presence of phytoplankton withtrue-colour imagery. These microscopic plant-likeorganisms sometimes reproduce so explosively thatthey can tint the water in shades of green or blue.

Image Credit: MODIS Land Rapid Response Team, NASA GSFC

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On June 17, 2021, Meteor M2 captured this image showing strong sunglint on the waters around Scotland and Ireland.

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NASA’s AIRS Tracks Record-Breaking Heat Wave in Pacific Northwest
JPL News

The AIRS instrument aboard NASA’s Aqua
satellite collected temperature readings in
the atmosphere and at the surface during
an unprecedented heat wave in the PacificNorthwest and western Canada that started
around June 26. The science instrument
mapped the dome of high pressure that settled
over the northwestern U.S. and western Canada
in late June, sending temperatures into theforties Celsius.
The unprecedented heat wave that started
around June 26 smashed numerous all-timetemperature records in the Pacific Northwest
and western Canada. NASA’s Atmospheric
Infrared Sounder (AIRS), aboard the Aqua
satellite, captured the progression of this slowmoving heat dome across the region from
June 21 to 30. These images from the AIRS
data show surface air temperature anomalies—
values above (red/purple) or below (blue) longterm averages. Surface air temperature is what
people feel directly when they are outside.
In many cases, the highs exceeded previous
temperature records by several degrees ormore. On June 28, Quillayute, Washington, set
an all-time high temperature record of 43°C,
shattering the old record of 37°C. Numerous
weather stations broke records on consecutive
days, showing the unprecedented nature ofthis extreme heat, which was also blamed fora number of fatalities. In British Columbia, thevillage of Lytton set a new all-time record for
Canada at 48°C on June 29, only to break it thenext day with a reading of 49°C.
AIRS, in conjunction with the Advanced
Microwave Sounding Unit (AMSU), senses
emitted infrared and microwave radiationfrom Earth to provide a three-dimensional
look at the planet’s weather and climate.
Working in tandem, the two instruments makesimultaneous observations down to Earth’s
surface.

AIRS image - June 21, 2021

AIRS image - June 26, 2021

With more than 2,000 channels sensing
different regions of the atmosphere, the systemcreates a global, three-dimensional map ofatmospheric temperature and humidity,
cloud amounts and heights, greenhouse gas
concentrations and many other atmosphericphenomena.
More information about AIRS can be found at:https://airs.jpl.nasa.gov/NASA Earth Observatory images by

AIRS image - June 30, 2021

Images credit: NASA/JPL-Caltech

www.geo-web.org.uk
https://www.jpl.nasa.gov/images/heat-wave-surface-temperature10

Sweden’s Siljan Ring
NASA Earth Observatory
Story by Kathryn Hansen

NASA Earth Observatory image by Lauren Dauphin, using Landsat data from the U.S. Geological Survey.

Covered with lakes, forests, and mountains, DalarnaCounty has been called “Sweden in miniature.” But
the same region that today draws people to its idylliclakeside villages and midsummer celebrations was
also the site of an ancient, catastrophic impact.
Around 380 million years ago, in the Late Devonian
period, an asteroid slammed into the land that is
now south-central Sweden. The impact left quite amark. Even after hundreds of millions of years oferosion, the scar is still recognizable. It is especiallyapparent when viewed from above.
The Siljan impact structure, or ‘Siljan Ring’, is visible
in this image, acquired on June 24, 2020, with
the Operational Land Imager (OLI) on Landsat 8.
Measuring more than 50 kilometres across, Siljan is
the largest-known impact structure in Europe andamong the 20 largest on Earth.

Surveys of the structure have shown that the groundis slightly raised up across parts of the crater’s
centre. It is surrounded by a ring-like graben, or
depression, which today is partially filled with water.
Lake Siljan, on the crater’s southwest side, is thelargest lake; it connects to Lake Orsa via a small
river.
People have lived near the crater for millennia
without knowing its cosmic origin. In the late 1960s,
scientists used drill cores to uncover the complex
and ancient geology deep below the ground.
Research at Siljan is ongoing today. In a 2019 study,scientists described how they used drill cores to findthat the deep, fractured rocks in the crater weresuitable for ancient life. A subsequent paper in 2021
described the fossilized remains of fungi discoveredat a depth of more than 500 metres.

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Heatwave conditions over much of England were observed by the NOAA 20 satellite in this image acquired on July 17, 2021.
Many areas experienced temperatures in the 30s Celsius, eliciting warnings from the Met Office.

www.geo-web.org.uk

12Frigid Weather in South Africa
MODIS Web Image of the Day

Image Credit: MODIS Land Rapid Response Team, NASA GSFCSouth Africa shivered under frigid winter weather assnow—and minimum temperature records—fell acrossthe country in late July 2021. According to the South
African Weather Service (SAWS), a series of cold fronts
sweeping across the country were responsible for thefalling temperatures, gusting winds, and snow. The firstcold front brought strong north-westerly winds and rain to
the southwestern parts of South Africa on July 19, with
precipitation in the form of snow along with bitterly cold
temperatures inland.
A second, more intense cold front escorted even colder
temperatures across much of the country beginning on
July 21. On July 23, local media reported that nineteen
records were smashed over the previous 24 hours,with several parts of South Africa recording their lowest
minimum or maximum temperature in recorded history.
On that day, temperatures in Kimberly (Northern Cape
province) dropped to -9.9°C and Johannesburg (Gauteng
province) saw -7°C. In the Eastern Cape, the town ofGrahamstown reported a maximum temperature of only
6.8°C.
The Moderate Resolution Imaging Spectroradiometer(MODIS) aboard NASA’s Terra satellite acquired this truecolour image of a sunny but frigid day in South Africa on
July 23. Snow sits atop the higher elevations of most of
the mountain ranges in the country and a broad swath ofsnow paints the Karoo region white, south of Sutherland,
Northern Cape province.

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A Summer of Fire-Breathing Smoke Storms
NASA Earth Observatory
Story by Adam Voiland

Figure 1 - This swarm of pyrocumulonimbus clouds along the Saskatchewan-Manitoba border on July 16, 2021.
Image: NASAIn 2000, atmospheric scientists from the U.S. Naval
Research Laboratory (NRL) first reported that smoke
plumes from intense wildfires could spawn towering
thunderstorms that channelled smoke as high or higher
than the cruising altitude of jet aeroplanes. These
pyrocumulonimbus (pyroCb), events wowed scientists atthe time. Prior to that discovery, only explosive volcanic
eruptions and extreme thunderstorms were thought to becapable of lofting material so high.
Though the workings of these smoke-infused storm
clouds have come into clearer focus, their increasingly
extreme behaviour in recent years has surprised andworried scientists who track them. The latest encounterswith these fire-breathing smoke clouds came in North
America in June and July 2021 during an unusuallywarm fire season that arrived early in Canadian and U.S.
forests.
Michael Fromm and David Peterson of NRL and a teamof colleagues from NASA and several other institutions
have used the Advanced Baseline Imager (ABI) on
the NOAA-NASA GOES weather satellites, as well as

sensors on other satellites, to identify 61 pyroCbs inNorth America this year as of July 29, 2021, about the
halfway point of the fire season.
Their observations included a remarkable outbreak of
10 pyroCbs along the Saskatchewan-Manitoba borderon July 16. It was more of the wildfire smoke storms
than scientists have ever observed in North America ona single day since they started tracking all of them withsatellites in 2013. In the ABI image shown in figure 1,
all of the marked clouds ended up generating PyroCbs,
though some were still in the pyrocumulus (pyroCu)
stage when the image was taken. Figure 2, overleaf,
shows an example of a small pyroCb rising above the
McKay Creek fire on June 30, 2021.
The July outbreak came two weeks after anotherunusual event—what Fromm called a ‘monster pyroCb’
that exploded on June 30 above the Sparks Lake fire inwestern Canada. A storm cell grew over a forest fire in
British Columbia and spread across more than 160,000
square kilometres, an area slightly larger than the stateof Georgia.

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Figure 2 - A small pyroCb rising above the McKay Creek fire on June 30, 2021.
Image: NASAAs it spread out, it sent a chimney of smoke up to
16 kilometres, according to data collected by the Multiangle Imaging SpectroRadiometer (MISR) on NASA’s
Terra satellite. Meanwhile, a GOES satellite observed
the storm unleashing extraordinary bursts of lightning.
After watching satellite clips of the storm blowing up andsmoke spreading widely as updrafts hit the stratosphere,
one meteorologist characterized the cloud’s behaviour as‘absolutely mind blowing.’
Scientists say it was the largest single pyroCb cloudthey have ever observed in North America. The North
American Lightning Detection Network recorded nearly
113,000 cloud-to-ground lightning strokes during theevent, a large amount for a storm in Canada. One

meteorologist calculated that this single pyroCb event
produced about five percent of Canada’s total annual
lightning all at once. Because smoke particles in pyroCbs
limit the size of water droplets, the thunderstorms
produce minimal rain. So the burst of lightning may
have sparked new fires, accelerated their spread, andre-energised the meteorological engine that created it in
the first place.
All of this played out during an unusually severe andodds-defying heatwave that pushed temperatures in
British Columbia to record levels (figure 3). Those
extreme temperatures would have been ‘virtually
impossible’ without global warming, according toscientists from the World Weather Attribution initiative.

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Figure 4 - Several pyroCbs are seen risingfrom smoke plumes above SE Australia inthis MODIS image from January 4, 2020.
Image: NASA

Figure 3 - The air temperature anomaly(heatwave) over British Columbia
Image: NASA“We’re seeing pyroCbs occur almost nightly now, andwe’re only halfway through the fire season,” said Peterson.
“This could get much worse before it gets better.”Spectroradiometer (MODIS) image above shows several
pyroCbs rising from smoke plumes that were part of that
outbreak.

With extreme fires and pyroCbs becoming more common,
Fromm and Peterson find themselves asking what it allmeans. “We are running projects to make it easier toforecast where pyroCbs are going to pop up. The hopeis that we can improve the systems that keep firefighters,
pilots, and people as safe as possible,” said Peterson.
“But we’re also watching how much smoke reaches thestratosphere and developing methods to quantify what itmeans for Earth’s radiative balance and climate.”

With enough smoke in the stratosphere, the cooling effectcould be sizable, perhaps even enough to cause global
temperatures to decline, much like the eruption of ash
from Mount Pinatubo famously did in the 1990s due tothe volcanic particles that lingered in the atmosphere.
The Australian fires delivered about 1/10th the mass ofcooling aerosols into the stratosphere than Pinatubo did. “Ifpyrocbs become more frequent, the climate impacts could
really start to add up,” said Fromm. “It’s something we will
be watching closely.”

Based on past events—including a “super outbreak” inDecember 2019 and January 2020 when pyroCbs wereeven more numerous (figure 4)—scientists know that thesmoke these events inject into the stratosphere can spreadout and behave like a massive shade, leading to temporary
regional cooling. The Moderate Resolution Imaging

NASA Earth Observatory images by Joshua Stevens and Lauren
Dauphin, using MODIS and GOES data from NASA EOSDISLANCE and GIBS/Worldview, Landsat data from the U.S.
Geological Survey, and GEOS-5 data from the Global Modellingand Assimilation Office at NASA GSFC.

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Malé, the Maldives
European Space Agency

Sentinel 2 image contains modified Copernicus Sentinel data (2019), processed by ESA, CC BY-SA 3.0 IGO

The Republic of Maldives consist of a chain ofaround 1200 small coral islands that are grouped
into clusters of atolls scattered across 90 000 square
kilometres of ocean. A number of these little islands
can be seen in the image, with the turquoise colours
depicting clear, shallow waters dotted by coral reefs
which contrasts with the dark colours of the Indian
Ocean.
Malé, located at the southern edge of the North
Malé Atoll, can be easily spotted in the right of

the image. The island is small enough to walkaround in approximately one hour, with most sights
concentrated on its northern shore. Malé is both a
trade and tourist centre, connected with Sri Lanka
and India by steamship lines, with several vessels
visible in the image.
With a population of more than 200 000 and an areaof around eight square kilometre, Malé is one of themost densely populated cities in the world, with thecity covering almost the entire island.

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Aerial view of the Malé viewed from the west
Image: Shahee Ilyas / Wikimedia Commons
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.

With more than 80% of the Maldives’ land standing
less than one metre above average sea level, theMaldives has the lowest terrain of any country in
the world. This makes the archipelago particularly
vulnerable to sea-level rise.
In response to this rising threat, the Maldives is
working on enhancing the resilience of the country’s
islands, which includes constructing the artificial
island of Hulhumalé—visible northeast of the airport
island of Hulhulé.
Hulhulé lies immediately northeast of Malé and isconnected to the latter by the 2.1 kilometre long
Sinamalé Bridge. This bridge, which carries two
car lanes and separate lanes for motorcycles andpedestrians, opened on August 20, 2018.
The island has been constructed by pumping sandfrom the sea floor onto a submerged coral platform,
that rises around two metres above sea level.
The reclaimed land provides some much-needed
space, and will also help meet the industrial andcommercial development of the Malé region.
Satellite data have shown that the global ocean
has risen, on average, three millimetres a year overthe last 25 years. Warming ocean waters, melting
glaciers and diminishing ice sheets are making rising
sea levels a real threat for low-lying islands such as
the Maldives.

This graph illistrates the three millimetre annual increase in sea
level rise at the Maldive Islands between 1993 and 2021.
Image: ESA

Following liftoff in November 2020, the Copernicus
Sentinel-6 Michael Freilich satellite, the mostadvanced mission dedicated to measuring sea-levelrise, is now fully operational, meaning that its data
are available to climate researchers, ocean-weather
forecasts and other data users. Learn more about
the Sentinel-6 mission, click the URL at the foot of
this page.
This image was captured by the Copernicus
Sentinel-2 mission – a two-satellite mission to supply
the coverage and data delivery needed for Europe’s
Copernicus programme.

https://www.esa.int/Applications/Observing_the_Earth/Copernicus/Sentinel-6/New_sea-level_monitoring_satellite_goes_live

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Fire Island, Cabo VerdeNASA Earth Observatory
Amber Turner, Jacobs, and Justin Wilkinson, Texas State
University, JETS Contract at NASA-JSC

The Cabo Verde island of Fogo
Astronaut photograph ISS063-E-54142 was acquired on July 23, 2020, with a Nikon D5 digital camera using a
focal length of 400 millimetres. It is provided by the ISS Crew Earth Observations Facility and the Earth Scienceand Remote Sensing Unit, Johnson Space Center.

This photo captures an astronaut’s view of Fogo,
an island 600 kilometres off the coast of West
Africa. The name Fogo translates from Portuguese
to English as ‘fire’. The name epitomises the volatilenature of the Cabo Verde (Cape Verde) volcanicislands.
Pico de Fogo is the highest peak in Cabo Verde,
towering 2829 metres above sea level. It is also thehighest peak in West Africa. Pico de Fogo is theactive cone at the summit of the Fogo stratovolcanothat forms the island. As seen from the International
Space Station, the semicircle of surrounding cliffs
marks the edge of the Cha das Caldeiras summit
caldera. Research by geologists shows that theentire east side of Fogo volcano slid into the sea in aprocess known as lateral collapse. That event, now
known as the Monte Amarelo landslide, formed thecaldera approximately 80,000 years ago.
Scientists using subsea backscatter sonar techniques
have been able to identify the landslide rubble on
the sea floor offshore of the east side of the island.
So much material slid off the volcano flank that thedebris field covers an area larger than the area of
Fogo Island itself. Landslides are common on active
volcanic islands—such as Fogo and the Hawaiian
islands—as the repeated burial of unconsolidated
rock debris by subsequent eruptions can create fault
zones. Acidic solutions can also form from volcanic
gases, and these can alter rock-forming minerals into
clay minerals, leading to weaker rock masses.

https://earthobservatory.nasa.gov/
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Sentinel 2C
Les Hamilton
Sentinel‑2A, the first member of ESA’s Copernicus
Earth observation satellite constellation (along with
Sentinel 2B) pased its sixth anniversery in orbit onJune 23, 2021. With a design lifetime of just sevenyears, ESA engineers are already preparing its
successor, Sentinel‑2C. With a likely launch early in
2024, this one tonne satellite recently commenced
a five month testing programme to determine its
fitness for the rigours of space. When the time comesto take Sentinel-2A out of service, Sentinel‑2C will
replace it, as will Sentinel‑2D eventually take overfrom Sentinel‑2B.
Like its forebears, Sentinel‑2C will carry a highresolution multispectral imager supporting 13 bands
in the visible, near infrared, and short wave infrared
regions of the spectrum. With a 290 kilometre swath
width and frequent revisit times, Sentinel‑2C will
provide unprecedented imagery of Earth to provide
information, mainly for agricultural practices and fortackling the global issue of food security. In addition,
the satellite’s imagery will also be important inmonitoring ice sheets and glaciers, coastal erosionand deforestation.
Right: Sentinel-2C being readied for testing
Image: ESA

Heavy winds, rain, and storm surge threatened the U.S. Northeast as Tropical Storm Henri approached. This natural
colour image acquired by the MODIS instrument aboard NASA’s Terra satellite at 15.45 UT on August 20, 2021 shows
Henri about 640 kilometres southeast of Charleston, South Carolina. Sustained winds at the time measured 100
kilometres per hour, just 15 kph below the threshold for a Category-1 hurricane.
NASA Earth Observatory image by Lauren Dauphin, using MODIS data from NASA EOSDIS LANCE and GIBS/Worldview

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Henri Soaks the Northeast
NASA Earth Observatory
Story by Michael Carlowicz

Henri did not reach the northeast U.S. coast at hurricane
force, but the slow-moving storm still left a soggy mark on
the region as it became a rare tropical cyclone to makelandfall in New England (see image on previous page).
Months of rain fell in a few hours across New Jersey, New
York, and several other states between August 21-23,
2021, landing on soils that were already soaked by anexcessively wet summer.
Tropical Storm Henri made landfall near Westerly, Rhode
Island, on August 22, with sustained winds of 95 kilometres
per hour and gusts to 10 kph. In anticipation of the storm,
the cities of Providence, Rhode Island, and New Bedford,
Massachusetts, raised storm surge barriers in their ports
for the first time since Hurricane Sandy in 2012 [1] . But thestorm surge never became as severe as feared.
Rainfall was a different story. Widespread accumulationsof 10 to 23 centimeters were recorded in New York, New
Jersey, Pennsylvania, and Connecticut. Much of thatrainfall fell to the western side of the storm, whereas theeastern and northern sides saw more moderate rainfall.
A broad satellite estimate of rain distribution is captured
in the map, which shows data from August 19–23. The
data are remotely-sensed estimates that come from theIntegrated Multi-Satellite Retrievals for GPM (IMERG), a
product of the Global Precipitation Measurement (GPM)satellite mission. Local rainfall amounts can be significantly
higher when measured from the ground.
Henri meandered across the Atlantic toward New Englandfor several days and thereafter moved slowly after landfall.
Some meteorologists pointed to a blocking ridge of highpressure over the North Atlantic that kept the storm frommoving east and northeast as it usually would. While still
well offshore, Henri became connected to other weather
systems along the East Coast that pulled in moisture fromthe outer edges of the storm to provoke downpours.
The soaking started half a day before Henri made landfall.
Gauges in New York City’s Central Park recorded 4.92 cm
of rainfall between 10 and 11 p.m. on August 21, anda total of 20.8 cm by the time the storm had passed on
August 23. Another 25.3 cm fell in Brooklyn. In New
Jersey, the town of Cranbury was soaked with 22.6 cm,
while Oakland caught 23.4 cm. Ardmore, Pennsylvania,
recorded 10.8 cm, while New London, Connecticut—justwest of the landfall—received 9.4 cm.
“Henri’s slow westward-then-eastward loop acrosssouthern New England over a period of more than
24 hours while still classified as a tropical cyclone
was extremely unusual if not unprecedented,” wrote
meteorologist Bob Henson in a blog post. “Nearly all
tropical depressions, tropical storms, or hurricanes in

Total Rainfall - August 19 - 23, 2021
NASA Earth Observatory image by Joshua Stevens, using
IMERG data from the Global Precipitation Mission (GPM) at
NASA/GSFC.

the region move more rapidly north or northeast, hauledtoward the Atlantic by strong upper-level winds more
typical at that latitude than the exceptionally weak steering
currents present on Monday.”The soaking rain from Henri fell on a region that was
already enduring one of its top three wettest summers onrecord. According to the National Weather Service, morethan 58 cm of rain had fallen on New York City sinceJune 1. Typically, the entire perior of June through August
brings just 30 cm of rainfall.
ReferenceSuper Storm Sandy Savages States
GEO Quarterly No 36, page 42 (2012)www.geo-web.org.uk

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Smoke billows from fires in Turkey
European Space Agency

Captured by the Copernicus Sentinel-3 mission on
July 30, 2021, this image shows smoke billowing fromseveral fires which had been burning for several days
along the southern coast of Turkey.
Over the weekend, tourists and local residents had
to be evacuated from Bodrum and Marmaris, withsome fleeing by boat as the flames crept closer tothe shoreline. At the time, southeast Europe wasexperiencing extremely high temperatures. Greece
was reported to be expecting an all-time European
record of 47°C. The heatwave, the result of a heatdome, has seen temperatures reach above 40°C in
many areas, and meteorologists expect the weather
to continue for some time, making it the most severe
heatwave since the 1980s.

Image contains modified Copernicus Sentinel data (2021), processed by ESA, CC BY-SA 3.0 IGO

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California’s Dixie Fire Keeps on Growing
NASA Earth Observatory
Story by Kathryn Hansen.

The Dixie fire in Northern California has surpassed the
Bootleg fire in Oregon to become the largest fire so far thisyear in the United States. As of August 6, 2021, the Dixie
fire had charred more than 1,750 square kilometres).

With wind gusts as high as 65 kilometres per hour thatday, the fire quickly advanced across the dry mountainvegetation. It burned through the historic Gold Rush era
town of Greenville.

On August 4, 2021, an astronaut on the International
Space Station shot a photo of the Dixie fire’s thick smoke
plume (figure 1). Figure 2, also acquired on August 4,
shows the fire as observed by the Enhanced Thematic
Mapper Plus (ETM+) on Landsat 7. It combines naturalcolour with shortwave-infrared light to cut through some ofthe smoke and highlight the active fire fronts. In this view,the hottest and most active parts of the fire are orangeyellow.

Notice that while most of the smoke is being carried
toward the north, some smoke hangs in the valleys andcanyons south of the active fire areas. Smoke, which cansink toward the ground during a temperature inversion,is especially apparent in the Feather River Canyon. Wind
blowing down the canyon carried some of the smoke
toward the Sacramento Valley.
The enormous blanket of smoke from the Dixie fire anddozens of others burning across the western U.S. is visible
in figure 3, acquired on August 6, 2021, by the GOES‑17
satellite. GOES-17 is operated by the National Oceanicand Atmospheric Administration (NOAA); NASA helps
develop and launch the GOES series of satellites.
Overnight (August 5 to August 6) the Dixie fire grew by
about 280 square kilometres to become the third-largest
fire on record in California. It is still less than half the sizeof the August Complex, which burned more than 1 million
acres in 2020.

Figure 1 - Photograph of the Dixie Smoke Plume from the ISS.
Astronaut photograph ISS065-E-220417 was acquired on
August 4, 2021 and is provided by the ISS Crew Earth
Observations Facility and the Earth Science andRemote Sensing Unit, Johnson Space Center.

Figure 2 - The Dixie Fire viewed from Landsat 7
NASA Earth Observatory image by Joshua Stevens, using
Landsat data from the U.S. Geological Survey.

NASA Earth Observatory images by Joshua Stevens,using Landsat data from the U.S. Geological Survey and
GOES 17 imagery courtesy of NOAA and the National
Environmental Satellite, Data, and Information Service.

Figure 3 - The Dixie Fire viewed from GOES‑17
NASA Earth Observatory image by Joshua Stevens, using GOES
17 imagery courtesy of NOAA and the National Environmental
Satellite, Data, and Information Service (NESDIS).

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Annular Solar Eclipse, June 20, 2021
John Tellick

On June 20 this year, an annular eclipse of the sun
took place over western Russia, Greenland, andnorthern Canada. Those of us at lower latutudes in
Asia, Europe and the United States saw a partial solar
eclipse—as seen in the above photo from SW London.

Figure 1
This NOAA 19 image was acquired at 08:10 UT on June 10,2021, and shows the Arctic ocean northwest of Svalbard underfull solar illumination.

Although this eclipse was nowhere total, the contrast
between solar illumination over the Arctic before (left)and during the eclipse (right) is clear from the twosatellite images below.

Figure 1
This Metop-C image was acquired at 10:52 UT on June 10, 2021,
and shows much reduced illumination over the Arctic ocean
northwest of Svalbard.

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2424

Add High Resolution Country Outlines to MeteorGIS images
Les Hamilton

One of the most popular features of the MeteorGIS
software system is the ability to add country outline
overlays to Meteor satellite images, particularly to clarify
the scene when cloud prevails. The Shape File provided
with the MeteorGIS installation package creates outlines at
50-metre resolution, which is generally satisfactory whenviewing entire images.
But when you zoom into a region with an intricately
detailed coastline—like the sea lochs and islands ofScotland’s west coast—the 50-metre Shape File gives avery poor representation of reality. To obtain fine detail you
must use Shape Files offering 10-metre resolution.
Download 10-metre Shape Files
To obtain these Shape Files, visit
https://www.naturalearthdata.com/downloads/

then locate the panel headed ‘Large scale data, 1:10m’
and click the green button labelled ‘Physical’.

This opens another screen where you will find the panel
shown below with a green ‘Download coastlines’ button.

This downloads the file ne_10m_coastline.zip. Unpacking
this file produces a set of six Shape Files. You only require
three of these, namely:			
ne_10m_coastline.dbf			
ne_10m_coastline.shp			
ne_10m_coastline.shx
Copy these three files into your MeteorGIS folder anddiscard the other three.
Modify the default.ini in the MeteorGIS folder
To bring these 10-metre country outlines into use you must
edit the default.ini file in the MeteorGIS folder. This option
is not available using the MeteorGIS_Configurator utility: it

Country outlines applied to a Meteor M2 image acquired onJune 12, 2015: 50 metre (above) and 10 metre (below).

continued on page 26

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Country outlines comparison over the Norwegian fjords in a Meteor M2 image acquired on June 12, 2015.
The image at left has the 50-metre overlay applied, that on the right uses the more detailed 10 metre overlay.

has to be done with a text processor such as Wordpad or
Notepad.
Load default.ini into Notepad and scroll well down to thesection headed ‘[Shapes] ‘ as illustrated below:[Shapes]shapesNumber=1[Shape0]filename=ne_50m_coastline.shp
color=000000
thickness=3
All that is required is to edit the ‘50’ to ‘10’, as shown
below, then save the edited version of the ini file.
[Shapes]shapesNumber=1[Shape0]filename=ne_10m_coastline.shp
color=000000
thickness=3
Job done! Next time you run MeteorGIS, provided you
have ‘Shapes’ active (by setting ShapesNumber in
MeteorGIS_Configurator’s Shapes tab to a value greaterthan zero), you will see the 10-metre country outline
overlay on your image. Note, there is no need to delete
the 50-metre files. You can always use them again byreversing the edit above.

Controlling the overlay using a New ini File
It is, of course a matter of user preference whether country
outlines are added to Meteor images or not. My personal
preference is not to add outlines when the satellite detailis clear to view. However, where my region of interest
is totally obscured by cloud, I like to be able to quickly
add country outlines in order to judge the local weather
situation.
To save the bother of editing my default ini filetime and time again, I made a copy of it, withthe 10-metre overlay option active, renamed it
coastlines.ini, and saved it in the MeteorGIS folder.
Once a Meteor M2 transmission has been processed byMeteorGIS, a batch file containing the code in the greybox at the foot of this page can reprocess the raw images
saved in the Meteor_M2 subfolder, and add the overlay.
Using Notepad, create a text file containing this line ofcode, and name it coastlines.bat (be sure to include
the space before each ‘/’ character) and save it in the
MeteorGIS folder. To reprocess your Meteor data, double
click this coastlines.bat file and MeteorGIS.exe will spring
into action and reprocess its data..
Important Note
Because MeteorGIS never overwrites its files, make surethat the FinalImages folder is emptied before running thebatch file. Otherwise no new files will be saved.

MeteorGIS.exe /nolive /composeauto /sat:M2 /config:coastlines.ini
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Violent Formation for Mistastin Lake
NASA Earth Observatory
Story by Adam Voiland

NASA Earth Observatory image by Lauren Dauphin, using Landsat data from the U.S. Geological Survey.

Skies were clear and the waters of Mistastin Lakewere placid when the Operational Land Imager (OLI)
on Landsat 8 captured this natural-colour image ofLabrador, Canada, on an autumn day in 2017.
The scene would have looked quite different about
36 million years ago when an asteroid smashedinto Earth and left an impact crater where the lake(called Kamestastin by the Innu people) now sits.
While erosion has changed and obscured some of
the features, a 50-metre wall still rings much of thecrater. Geologists estimate the crater originally had
a diameter of about 28 kilometres—about twice its
current size.

Parts of the central peak are also visible in the lakeas Horseshoe Island. These mound-like features
are often found in the centre of large craters as a
product of the melting and rebound of subsurface
rocks. Meanwhile, the elongated, ellipticalappearance of the crater is a result of periods when
glaciers slid across this area during several ice ages.
Based on the presence of an unusual diamondlike mineral called cubic zirconia, the asteroid
impact must have heated rocks at the site to atleast 2370°C. That would be the hottest-known
temperature recorded by a surface rock on Earth,according to one team of researchers.

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27

Summer Colour in Northern Seas
NASA Earth Observatory
Story by Kathryn Hansen

In mid-June 2021, hints of aphytoplankton bloom brewed
off the coast of Newfoundland,
Canada. In the following weeks,
the faint patch transformed intoa brilliant blue expanse as thenumber of microscopic plant-likecreatures exploded.
The bloom was in full swing
on August 5, 2021, when theModerate Resolution Imaging
Spectroradiometer (MODIS) on
NASA’s Aqua satellite acquired
figure 1. Clouds are common over
the Labrador Sea, and this day
was no exception. But areas eastand southeast of Newfoundland
were clear enough for satellites todetect the stunning blue display.
Faint traces of the bloom werestill visible amid the clouds on
August 23.

Figure 1 - North Atlantic on August 5, 2021.

The colour of the ocean here isa good indication that the bloom
is composed of coccolithophores,
probably Emiliania huxleyi. The
phytoplankton are covered inchalky calcite plates that arehighly reflective, which make theocean surface appear milky blue.
Each cell is just a few nanometersacross, but when enough of themcongregate over a large area they
become visible from space.
The region’s currents andcirculation patterns help enrich
the water with nutrients, which
can enhance the productivity ofphytoplankton when combinedwith sunlight. The organisms
become food for zooplankton,shellfish, and other marine
creatures, which has helped makethis region one of the richest
fishing grounds in the world.
It remains to be seen if
coccolithophores will persist into
September as they did in 2019
and again in 2020. In previous
years, E. huxleyi has been mostFigure 2 - Barents Sea on August 9, 2021.

abundant around mid-summer
but less common in autumn.
Meanwhile, about 5,000
kilometres away, in the Barents
Sea, a bloom that dazzled in
mid-July continued to put on adisplay. Figure 2 was acquired on
August 9, 2021, with the Visible
Infrared Imaging Radiometer
Suite (VIIRS) on the NASA-NOAA

Suomi NPP satellite. Traces of thebloom were still visible over a
week later on August 18.
This bloom is also most likely
dominated by coccolithophores.
E. huxleyi is common here fromaround late July into autumn,
replacing blooms of diatoms
that thrive in spring and earlysummer.

NASA Earth Observatory images by Joshua Stevens, using MODIS and VIIRS data fromNASA EOSDIS LANCE and GIBS/Worldview and the Suomi National Polar-orbiting Partnershipwww.geo-web.org.uk

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