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Earth Matters

Image Credit: NASA Earth Observatory/Aqua/MODIS

As powerful downslope winds sent the deadly Camp Fire raging through bone-dry vegetation in northern California on November 8, 2018, sensors on the ground and in space began to detect sharp increases in air pollution downwind of the inferno.

From space, the Moderate Resolution Imaging Spectroradiometer (MODIS) and Visible Infrared Imaging Radiometer Suite (VIIRS) sensor observed expansive smoke and aerosol plumes over California’s Central Valley and coast soon after the fire began. Likewise, the Ozone Mapping Profiler Suite (OMPS) on Suomi NPP observed unusually high aerosol levels, and the Measurement of Pollution in the Troposphere (MOPITT) on Terra picked up strong carbon monoxide signals from the fire.

Image Credit: Purple Air

Meanwhile on the ground, atmospheric scientists Pawan Gupta, Robert Levy, Prakash Doraiswamy, and Olga Pikelnaya have been keeping a close eye on air quality data from a network of low-cost sensors distributed throughout the region. These sensors measure the mass concentration of fine particulate matter (PM2.5). Some stations measured PM2.5 values higher than 500 micrograms per cubic meter, which is about 40 times higher than the level considered safe to breathe.

“On November 9th, due to favorable wind direction, most of the smoke was confined to a smaller region north of San Francisco, but the wind direction changed on the 10th, and smoke spread over a much larger region,” noted Gupta, who is based at NASA’s Marshall Space Flight Center and works with NASA’s SERVIR and ARSET programs. “On the 11th and 12th, the wind direction again changed, and most of the smoke blew over the ocean.”

Gupta is involved in an ongoing effort to deploy and test low-cost commercial air quality sensors to see how well their measurements compare with standard EPA measurements and NASA satellite observations. The ground-based sensors that are part of official state and federal government observing networks cost several thousand dollars each, but the new generation of sensors cost just a few hundred dollars—cheap enough that Gupta thinks they could proliferate and potentially be used to help fill in crucial gaps, particularly in countries with few air quality sensors.

Image Credit: NASA Earth Observatory/Landsat 8/OLI

“The low-cost sensors have performed as expected, though with varying accuracy for certain types of particles,” said Gupta. “Going forward, we hope to use what we learn from them to improve the techniques scientists use to derive levels of particulate matter at the surface from the entire column aerosol measurements observed by satellites.”

So far, Gupta and his colleagues have deployed about 40 low-cost sensors in California. Next summer, they plan to add hundreds of additional sensors in New Delhi, an area that regularly gets hit with dust storms and smoke from agricultural burning. They also plan to deploy sensors in North Carolina, an area with relatively clean air.

Citizen scientists interested in air quality can get involved in the project. Gupta and colleagues from RTI International, South Coast Air Quality Management District, NASA, and other institutions are recruiting volunteers to host the low-cost sensor and share the results with the experts.

Further Reading:
Air Quality Citizen Science, Project Goals and Overview
EOS, New Strategies to Protect People from Smoke During Wildfires
KVPR, NASA’s JPL Using Fresno As A Test Bed For Air Quality Research
Geohealth, Impact of California Fires on Local and Regional Air Quality: The Role of a Low‐Cost Sensor Network and Satellite Observations

Highlights from The Earth Observer

November 7th, 2018 by Adam Voiland

A new edition of The Earth Observer, a bi-monthly publication that covers the nuts-and-bolts of NASA’s Earth Observing System, is out. Here are a few excerpts, along with some musical headlines that may get you humming as you read. You can download the full issue here. Back issues here.

ICE ICE BABY
The Advanced Topographic Laser Altimeter System (ATLAS), the lone instrument on ICESat-2, successfully fired its laser on September 30 after the mission operations team completed testing of the spacecraft and opened the door protecting the optics. The primary science mission for ICESat-2 is to gather enough observations to estimate the annual height change of the Greenland and Antarctic ice sheets to within four millimeters. Hundreds of billions of tons of land ice melt into the ocean annually, raising sea levels worldwide. In recent years, meltwater from Greenland and Antarctica alone has raised global sea level by more than a millimeter a year, and the rate is increasing.

THIS LANDSAT IS YOUR LANDSAT
In January 2008, the U.S. Geological Survey and NASA decided to open the full Landsat image archive for public access on a non discriminatory, no-cost basis. This change in Landsat’s data policy ushered in a new era of Landsat data uses and applications while also revolutionizing the way Landsat has been woven into scientific discovery, economic prosperity, and public policy for management of land and water resources across a range of scales.

DEVELOPING SATELLITE SKILLS FOR 525,600 MINUTES (TIMES TWENTY)
From 1998 to the current 2018 fall term, the NASA DEVELOP National Program has engaged 4,671 participants who have conducted 931 projects. The program bridges the gap between science and society by demonstrating how NASA Earth Science data can be applied to environmental decision making. These projects have demonstrated the applications of NASA Earth observations to a wide variety of sectors, addressing topics such as drought monitoring, vector-borne disease risk, water-quality assessments, pre- and post-wildfire mapping, agriculture monitoring, and critical habitat identification.

I CAN SEE CLEARLY NOW

The first Earth Science Decadal Survey identified CLARREO as a Tier-1 (i.e., highest) priority mission for development. The CLARREO Pre-Formulation Mission, referred to herein as the “Full” CLARREO mission, was recommended to better understand climate change. The foundation of CLARREO is the ability to produce highly accurate climate records to test climate projections in order to improve models and enable sound policy decisions.

Famous Rectangular Iceberg’s Rough Journey

November 5th, 2018 by Kathryn Hansen

This wide view, acquired on October 14, 2018, by the Landsat 8 satellite, shows the area where part of the rectangular iceberg was photographed from NASA’s DC-8.

This rectangular iceberg made headlines after it was photographed on October 16, 2018, during an Operation IceBridge science flight. Credit: NASA/Jeremy Harbeck

The sharp-angled iceberg that made headlines in late October 2018 had a longer, rougher journey than was initially thought.

The iceberg was spotted on October 16, 2018, during a flight for Operation IceBridge—NASA’s long-running aerial survey of polar ice. During that day’s survey of glaciers and ice shelves along the northern Antarctic Peninsula, scientist Jeremy Harbeck spotted the compelling berg. Harbeck explained in a NASA story his reason for taking the picture:

“I was actually more interested in capturing the A68 iceberg that we were about to fly over, but I thought this rectangular iceberg was visually interesting and fairly photogenic, so on a lark, I just took a couple photos.”

Not only were the edges of the iceberg extremely straight, but the two corners appeared “squared off” at right angles. The berg was so clean-cut that it was reasonable to assume it might have very recently calved from the Larsen C ice shelf. That’s the same ice shelf that spawned A-68, the trillion-ton iceberg that broke away in July 2017.

It turns out, however, that the rectangle berg actually has had a much longer journey. Scientists used images from Landsat 8 and the European Space Agency’s Sentinel-1 to trace the berg back to its origins. They found that it calved from the ice shelf’s new front in early November 2017, just a few months after A-68 broke away. The image below, tweeted November 9, 2018, by Stef Lhermitte of Delft University of Technology, shows the small, newly calved icebergs. The rectangle iceberg—which was about 4 kilometers long at the time—appears just north of a curved berg. Both were about a third of the way down the new front of the Larsen C.

The rectangle berg then began a northward journey, navigating the newly open water between the Larsen C ice shelf and Iceberg A-68. Collision threats were everywhere: A-68 could smash into the little bergs at any time, and smaller bergs could collide with each other.

The berg cruised all the way north and through a narrow passage between the A-68’s northern tip and a rocky outcrop near the ice shelf known as Bawden Ice Rise. NASA/UMBC glaciologist Chris Shuman likens this zone to a nutcracker. A-68 has repeatedly smashed against the rise and caused pieces of ice to splinter into clean-cut geometric shapes. An area of geometric ice rubble is visible in the Landsat 8 image (top and below) from October 14, 2018, two days before the IceBridge flight.

The once-long rectangle berg did not make it through unscathed; it broke into smaller bits. The iceberg in Harbeck’s photograph, circled in the annotated Landsat 8 satellite image, appears closer to the shape of a trapezoid. The trapezoidal berg is about 900 meters wide and 1500 meters long, which is tiny compared to the Delaware-sized A-68.

By November 2018 the iceberg had moved out of the rubble zone and into open water. Shuman noted: “Now it’s just another iceberg on its way to die.”

October Puzzler

October 26th, 2018 by Kathryn Hansen

Every month on Earth Matters, we offer a puzzling satellite image. The October 2018 puzzler is above. Your challenge is to use the comments section to tell us what we are looking at and why it is interesting.

How to answer. You can use a few words or several paragraphs. You might simply tell us the location. Or you can dig deeper and explain what satellite and instrument produced the image, what spectral bands were used to create it, or what is compelling about some obscure feature in the image. If you think something is interesting or noteworthy, tell us about it.

The prize. We can’t offer prize money or a trip to Mars, but we can promise you credit and glory. Well, maybe just credit. Roughly one week after a puzzler image appears on this blog, we will post an annotated and captioned version as our Image of the Day. After we post the answer, we will acknowledge the first person to correctly identify the image at the bottom of this blog post. We also may recognize readers who offer the most interesting tidbits of information about the geological, meteorological, or human processes that have shaped the landscape. Please include your preferred name or alias with your comment. If you work for or attend an institution that you would like to recognize, please mention that as well.

Recent winners. If you’ve won the puzzler in the past few months or if you work in geospatial imaging, please hold your answer for at least a day to give less experienced readers a chance to play.

Releasing Comments. Savvy readers have solved some puzzlers after a few minutes. To give more people a chance to play, we may wait between 24 to 48 hours before posting comments.

Good luck!

The New UN Climate Report in One Sentence

October 19th, 2018 by Adam Voiland

 

In October 2018, the Intergovernmental Panel on Climate Change (IPCC) released yet another sobering report about the planetary disruption happening because of all the carbon human activity puts into the atmosphere.

Many parts of the world are already seeing rising sea levels, hotter temperatures, more extreme precipitation and droughts, more acidic oceans, and faster rates of extinctions, the scientists said. And without dramatic reductions in carbon emissions to keep warming below 1.5 degrees Celsius, the problems are going to get far worse.

In just one sentence, Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies, captured the essence of the report. “The key thing to remember is that it’s clear that the best time to have reduced emissions was 25 years ago,” he said during an interview with PBS News Hour. “But the second best time to reduce emissions is right now.”

Like any good scientist, Schmidt is always quick to give credit where credit is due. In this case, he noted that what he said on television was a riff on something that renowned Kenyan marathoner Eliud Kipchoge once said. “The best time to plant a tree was 25 years ago. The second-best time to plant a tree is today,” The New York Times quoted the marathon world record holder as saying.

If you are wondering what the IPCC authors based their findings on, there is no shortage of information to explore. Each chapter of the report has a supplementary information section with dozens of references that detail the evidence the scientists used to draw their conclusions.

For more details, the IPCC also put together a succinct summary for policy makers, a press release, headline statements, and FAQs. Also, below are a few other good resources if you’re looking to understand some of the basics about climate change.

+NASA’s Global Climate Change Evidence Page
+NASA Earth Observatory’s Global Temperatures World of Change
+NOAA Climate Education Resources
+Skeptical Science Climate Change Myths

 

According to an ongoing temperature analysis conducted by scientists at NASA’s Goddard Institute for Space Studies, the average global temperature on Earth has increased by about 0.8° Celsius (1.4° Fahrenheit) since 1880. Two-thirds of the warming has occurred since 1975, at a rate of roughly 0.15-0.20°C per decade. Read more about this map here.

 

If there was ever a satellite that deserves an award for longevity, it’s Terra. Designed for a mission of 6 years (or 30,000 orbits), the bus-sized spacecraft continues to cruise 705 kilometers (438 miles) above Earth’s surface nearly 19 years after launch. The spacecraft officially surpassed 100,000 orbits on October 6, 2018. To celebrate, here are ten things to know about the intrepid Earth-observing satellite. Click on each image to find out more.

1. Terra had to be designed from scratch. Unlike many of the smaller satellites that preceded it, engineers couldn’t riff off of an existing design.

 


2. The bus-sized spacecraft carries five scientific sensors — MODIS, MOPITT, MISR, ASTER, and CERES. All of them continue to send back useful data.

 

3. The MODIS sensor captures stunning images of hurricanes, wildfires, volcanoes, dust storms, oil spills, and other hazards.

 

4. Using MOPITT, atmospheric scientists have tracked global trends in carbon monoxide for nearly two decades. The good news: concentrations of the toxic air pollutant are declining.

 

5. Likewise, they have used the CERES sensor to measure whether Earth’s reflectivity—or albedo—has changed. Despite some fluctuations, there does not appear to be a trend.

 


6. The MISR sensor can detect the height of volcanic plumes, smoke plumes, dust plumes, and other aerosols. This is key to understanding where plumes will go and whether they will pose a threat to people on the ground.

 


7. Terra orbits 705 kilometers (438 miles) above the surface, about the distance between Boston, MA, and Washington, D.C.

 


8. A widely used global digital elevation map is based on data collected by ASTER.

 


9. Experts use Terra MODIS observations of NDVI — a measure of the greenness of plants — to help anticipate food shortages.

 

10. While in space, Terra has traveled the equivalent of 2.5 billion miles — nearly the distance to Neptune.

First Photons from ICESat-2

October 5th, 2018 by Kathryn Hansen

“Pho,” a cartoon character representing a photon of light from ICESat-2, illustrates how the science mission works. Watch the video here. Credit: NASA/Goddard/Savannah College of Art and Design et al.

The successful launch of a satellite is an exciting step for the scientists and engineers who have spent years dedicated to a mission. But there are still many more boxes to be checked, and anticipation builds as a satellite’s instruments are turned on and they produce what scientists call “first light” — the first time a satellite opens its “eyes” and delivers preliminary images or data.

After the successful launch of NASA’s Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) on September 15, 2018, “first light” was not a natural-color image of Earth like those that come from satellites such as Terra, Aqua, or Landsat. Rather, the satellite’s sole instrument—the Advanced Topographic Laser Altimeter System (ATLAS)—acquired measurements of surface elevation. The laser fired for the first time on September 30, and returned its first height measurements from across the Antarctic ice sheet on October 3.

This visualization of ICESat-2 data shows the first set of height measurements from the satellite as it orbited over the Antarctic ice sheet. Credit: NASA’s Goddard Space Flight Center

This elevation measurement, acquired on October 3, shows the height of the Antarctic ice sheet along a path starting in East Antarctica, passing close to the South Pole, and ending in West Antarctica. As explained in a NASA story about the measurement:

“When scientists analyze the preliminary ICESat-2 data, they examine what is called a “photon cloud,” or a plot of each photon that ATLAS detects. Many of the points on a photon cloud are from background photons — natural sunlight reflected off Earth in the exact same wavelength as the laser photons. But with the help of computer programs that analyze the data, scientists can extract the signal from the noise and identify height of the ground below.”

These charts show the first photon returns from the instrument’s six beams as the satellite orbited over Antarctica. The green lines represent the number of photons detected. The X axis indicates the amount of time it took the photons to get from the satellite to the ground and back again. Credit: Megan Bock/NASA’s Goddard Space Flight Center.

Donya Douglas-Bradshaw, the project manager for the ATLAS instrument, said in the NASA story:

“We were all waiting with bated breath for the lasers to turn on and to see those first photons return. Seeing everything work together in concert is incredibly exciting. There are a lot of moving parts and this is the demonstration that it’s all working together.”

New Tools to Boost Access to NASA Earth Science Data

October 1st, 2018 by Mike Carlowicz

NASA has funded five new projects to develop tools and technology to make the agency’s massive Earth science datasets more accessible and user-friendly.

Wake up. Turn on laptop. Start processing airborne data of the Adirondack forests in New York. Make Coffee. Eat Breakfast. Fasten the open laptop’s seatbelt in the passenger seat as it continues to crunch numbers. Drive to work.

NASA Earth science datasets provide different perspectives and information on our planet, as seen here in this data visualization of observations of Hurricane Matthew in October 2016. Credits: NASA’s Scientific Visualization Studio

That used to be Sara Lubkin’s morning routine as an early career scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Once at work, she would use her desktop computer, while her laptop diligently spent the next 12 hours processing airborne instrument data for the relevant information she needed to study invasive pests of hemlock trees.

“I’m not a computer scientist, I’m an Earth scientist,” said Lubkin, who now works as a program officer for NASA Earth Science Data Systems’ Advancing Collaborative Connections for Earth Systems Science, or ACCESS program. But her experience as a researcher is not unique.

Spending large chunks of time simply getting Earth science data into a usable form for analysis is a common situation for researchers working with the big datasets that come from NASA field, airborne and satellite missions. Downloading huge files, converting data formats, locating the same study areas in multiple datasets, writing code to distinguish different land types in a satellite image – these types of tasks eat into time scientists would rather be using to analyze the actual information in the data.

That’s where the ACCESS program comes in. Part of the Earth Science Data Systems division since 2005, ACCESS finds innovative ways to streamline that cumbersome processing time. The program funds two-year research projects to improve behind-the-scenes data management and provide ready-to-use datasets and services to scientists, Lubkin said.

Sara Lubkin worked with NASA’s big data sets studying invasive pests in Adirondack hemlock trees as part of NASA’s Applied Sciences DEVELOP program, which addresses environmental and public policy issues through interdisciplinary research projects that apply the lens of NASA Earth observations to community concerns around the globe. Credit: Sara Lubkin

In June, NASA selected five teams of NASA, university and commercial computer science researchers from the 2017 round of submissions in a range of projects that will use machine learning, cloud computing and advanced search capabilities to develop tools to improve the behind-the-scenes management for selected NASA datasets.

“We continually invest in development and evaluation of the newest technologies to improve science data systems,” said Kevin Murphy, program executive for NASA’s Earth Science Data Systems at NASA Headquarters in Washington. But more than that, they want to make sure that the tools and technology help real scientists address real problems.

Each ACCESS project has Earth scientists and computer scientists involved from beginning to end, Murphy said. “With the ACCESS program, we’re really trying to understand, for example, how ocean currents work, but we’re trying to do that now with data that’s so large that we need a team of experts who can work together to solve the big science and big data questions.”

The projects will complement data management, distribution and other services provided by the Earth Observing System Data and Information System (EOSDIS), which manages and stores NASA data collected from Earth-observing satellites, aircraft and field campaigns. EOSDIS has 12 interconnected data and archive centers located across the United States, which are organized by discipline. Currently, these centers host 26 petabytes of Earth datasets – that’s 26 million gigabytes, or enough data to need 52,000 computers each with 500 gigabytes of storage space. That number is expected to grow to 150 petabytes within five years with the launch of new satellites.

“Satellite data is big data,” said Jeff Walter, one of the ACCESS 2017 principal investigators and lead engineer for Science Data Services at the Atmospheric Science Data Center at NASA’s Langley Research Center in Hampton, Virginia. “It’s very complex and sometimes difficult to use, even for expert users. In addition to the volume, which makes it difficult for users to acquire, store and manage, there’s also the complexity of both the format and content. Users often have to spend a lot of time understanding how the data is organized and what the various parameters represent.”

Walter’s project is one of three that will use cloud computing to alleviate download and storage issues for users. Starting with two atmospheric datasets, his team will also be developing a way to convert satellite data formats into those that can be read by commercial geospatial information system (GIS) software.

“Our project aims to lower the barrier to entry for a potential new user community who might find novel ways to use this data, and who are more familiar with GIS types of tools,” Walter said.

The two other cloud computing projects will be developing open source processing and analysis tools, including one designed for ocean datasets. A fourth project will use machine learning to detect changes over time in land observations, starting with the detection of landslides, floods and uplift caused by volcanic activity. The fifth project will develop an automated method for lining up datasets that observe the same location so researchers can combine more than one type of information about a place.

NASA has 26 Earth-observing satellites monitoring the vital signs of our home planet. Along with airborne and ground Earth science missions, their data is stored and managed by the Earth Observing System Data and Information System. Credit: NASA

Upon completion, the ACCESS researchers will work closely with EOSDIS teams to incorporate their advancements into the data centers’ day-to-day operations. Once those new tools are in place, that’s when the real power of open and freely available Earth science datasets can flourish, according to Murphy. Easy-to-use data means it gets into the hands of decision-makers, non-governmental organizations, scientists studying related applications and researchers in different fields that may have new uses for it.

“When you make these products open and accessible, you have a lot of unintended, good scientific consequences,” Murphy said, citing examples that include detecting groundwater movement from space, rapid wildfire detection and using night lights to study human energy use. “NASA has a lot of very valuable information, and the ACCESS program really tries to help scientists to not only address primary science questions but also help us understand our environment and plan for our future.”

To learn more about ACCESS, visit https://earthdata.nasa.gov/community/community-data-system-programs/access-projects

To learn more about NASA’s Earth Science Data Systems, visit https://earthdata.nasa.gov/

Walking on Venezuela’s Last Glacier

September 27th, 2018 by Kathryn Hansen

The retreat of Humboldt Glacier—Venezuela’s last patch of perennial ice—means that the country could soon be glacier-free. We featured the glacier in August 2018 as an Image of the Day showing how it changed between 1988 and 2015.

Satellite images can tell you a lot about a glacier, but direct measurements by people on the ground provide a unique, important perspective, especially for glaciers as small as Humboldt. Carsten Braun, a scientist at Westfield State University, last surveyed the glacier in 2015. He talked about what it was like to stand on Venezuela’s last glacier.

The Operational Land Imager (OLI) on Landsat 8 acquired this natural-color image of the glacier on January 6, 2015.

These photographs show the ground-based view of Humboldt Glacier in 2015. Photos by Carsten Braun.

What things were you measuring during the 2015 survey?

This was a very ‘low-tech’ trip: just me and a guide. The approach to the glacier takes two days of very rough hiking with big packs. That gets you to base camp at Laguna Verde below the glacier.

To get to the glacier takes another three hours on rough terrain. This is definitely popular with climbers. They cross the Humboldt Glacier and then summit Pico Humboldt.

I did the same thing in 2009 and 2011: I walked around the glacier right on the margin with a simple GPS receiver to make a map of it. That sounds a lot easier than it is. Walking right on the edge of a glacier can be difficult and dangerous. This was definitely both!

What was the ice like? Parts of it look like snow or slush.

This glacier is little different than what you may have experienced. It is tiny and does not have an accumulation area. The surface is 100 percent ice everywhere, just covered in some parts in wet seasonal snow that will melt away. Basically that means that the Humboldt Glacier has no means to ‘add’ mass (‘eat’) and continuously loses mass everywhere (‘fasting’). Obviously, that’s not sustainable.

 

Photos by Carsten Braun.

Do you remember what you were thinking while hiking on the country’s last glacier?

I was definitely considering the impacts of losing this glacier. It has little ‘practical use’ today, as it is so small and pretty much irrelevant for water supply. Its disappearance would not impact water resources much, if at all. That’s much in contrast with countries like Peru and Bolivia, where glacier recession already creates huge problems for water resources, hydro-power, etc.

The impact in Venezuela is more at a spiritual level. The mountain chain is was named Sierra Nevada de Mérida (snowy mountain range of Mérida) because of its glacier cover. Now it will be gone soon and may never come back again. (Well, that’s up to us humans to decide.) And with that, the reality of these mountains will change. The lack of glaciers will be the ‘new normal.’ It’s a little bit like losing a species: once it’s gone, you never realize that it is missing.

 

September Puzzler

September 26th, 2018 by Kathryn Hansen

Every month on Earth Matters, we offer a puzzling satellite image. The September 2018 puzzler is above. Your challenge is to use the comments section to tell us what we are looking at and why this place is interesting.

How to answer. You can use a few words or several paragraphs. You might simply tell us the location. Or you can dig deeper and explain what satellite and instrument produced the image, what spectral bands were used to create it, or what is compelling about some obscure feature in the image. If you think something is interesting or noteworthy, tell us about it.

The prize. We can’t offer prize money or a trip to Mars, but we can promise you credit and glory. Well, maybe just credit. Roughly one week after a puzzler image appears on this blog, we will post an annotated and captioned version as our Image of the Day. After we post the answer, we will acknowledge the first person to correctly identify the image at the bottom of this blog post. We also may recognize readers who offer the most interesting tidbits of information about the geological, meteorological, or human processes that have shaped the landscape. Please include your preferred name or alias with your comment. If you work for or attend an institution that you would like to recognize, please mention that as well.

Recent winners. If you’ve won the puzzler in the past few months or if you work in geospatial imaging, please hold your answer for at least a day to give less experienced readers a chance to play.

Releasing Comments. Savvy readers have solved some puzzlers after a few minutes. To give more people a chance to play, we may wait between 24 to 48 hours before posting comments.

Good luck!

Answer: The image shows a detailed view of the Albanov Ice Cap on October Revolution Island. The island is part of the Severnaya Zemlya archipelago in the Russian high Arctic. Many of the area’s ice caps, including Albanov, contain snow and ice that has melted and refroze, visible as the blue areas ringing the ice caps. Congratulations to Bananaft for correctly identifying the location, and to Maria Bolton and Aureliano for mentioning ice melt. Read more about the image in our October 1, 2018, Image of the Day