By Michon Scott
In 1976, the United States celebrated its bicentennial, disco topped the charts, and no one had yet seen a Star Wars movie. That same year, the National Snow and Ice Data Center (NSIDC) opened its doors.
The next half-century transformed both the planet and the ways scientists observe it. Global population nearly doubled to 8.2 billion, Earth-observing satellites multiplied, computing power soared, and NSIDC grew from a two-person staff reporting to founding director Roger Barry into an organization of roughly 85 employees (See Our History for a detailed timeline.)
The technological change over that time was even more dramatic. Initially named the World Data Center (WDC-A) for Glaciology, NSIDC started as a small library. Its holdings were mostly on paper. To fit information into a smaller space, the leading technology included microfilm and microfiche—miniature images of paper documents stored on rolls or cards of film.
“One of my favorite artifacts from NSIDC’s early days is a microfiche reproduction of the paper ‘Problems associated with large scientific data bases,’” said NSIDC Director Mark Serreze. The microfiche reproduction sits on the same bookshelf in his office as other vintage data-storage devices, including a magnetic tape reel roughly a foot in diameter, and a supersized floppy disk measuring roughly 8 inches across.
NSIDC’s paper-based library soon changed. Before long, NSIDC became a data repository for satellite observations, aerial photography, fieldwork records, Indigenous perspectives, and rescued data. Throughout, NSIDC employed a staff of scientists and data experts who could interpret the data center’s vast holdings and make science understandable to students, teachers, planners, politicians, and taxpayers.
How Earth-observing technologies have advanced
Field expeditions, ship surveys, and local records of snow and ice go back centuries. Beginning in the twentieth century, aerial photographs also shed light on the planet’s ever-changing surface, but stitching together aerial photographs into reliable maps was complex and expensive.
Satellite technology began to change Earth observation nearly two decades before NSIDC opened. The Soviet Union launched Sputnik 1 in 1957, followed in 1960 by the United States’ TIROS-1, which demonstrated the potential of satellites for observing weather. NASA’s Nimbus missions followed, and Landsat 1 launched in 1972, starting a decades-long satellite record that continues today.
NOAA launched the first Geostationary Operational Environmental Satellite (GOES-1) in 1975. Geostationary satellites remain positioned over the same part of Earth, making them valuable for tracking weather. Observing Earth’s polar regions, however—where much of NSIDC’s data and research are focused—needs different, lower-altitude orbits.
Polar-orbiting satellites upgraded Earth observation in 1978—two years after NSIDC started. Polar-orbiting satellites had made earlier observations, including Landsat, starting in 1972, and NOAA satellites, beginning in 1966. But the Nimbus-7 satellite, launched on October 24, 1978, began providing a long-term, consistent polar-observation record.
Nimbus-7 carried the Scanning Multichannel Microwave Radiometer (SMMR) sensor, and starting October 25, 1978, SMMR observed the whole globe every two to three days. Those observations continued until August 20, 1987. Starting July 9, 1987, the Special Sensor Microwave/Imager (SSM/I) took daily observations. Data from those and many other polar-orbiting satellites found a distribution hub at the NASA NSIDC Distributed Active Archive Center, which was formalized in 1993.
The satellite sensors NSIDC has relied on for sea ice measurements have typically been passive microwave sensors. Rather than bouncing a beam of energy off Earth’s surface, these sensors simply observe energy coming from the planet, in the microwave portion of the electromagnetic spectrum. Although invisible to human eyes, a sensor operating in that portion of the electromagnetic spectrum “sees” sea ice through clouds and darkness—including the months-long night of polar winter.
More polar-orbiting instruments followed, including AVHRR, first launched in 1978; NASA’s MODIS sensors aboard Terra and Aqua, beginning in 1999 and 2002; and VIIRS, which NASA and NOAA began using in 2011 to supplement the MODIS record. Together, these increasingly capable instruments provided more frequent and detailed observations of Earth’s surface.
Laser altimeters offered yet another perspective on changing icy regions.
NASA’s Geoscience Laser Altimeter System onboard NASA's Ice, Cloud, and land Elevation Satellite (ICESat/GLAS) took observations from 2003 to 2010. In 2018, NASA’s Advanced Topographic Laser Altimeter System instrument began flying aboard the Ice, Cloud and land Elevation Satellite-2 (ICESat-2/ATLAS). Both GLAS and ATLAS sent laser pulses toward Earth, measuring the amount of time required for pulses to return to the sensor’s receiver. Whereas ICESat/GLAS sent 40 pulses per second, ICESat-2/ATLAS sends 10,000. These laser altimeters have provided precise measurements of surface elevations, although over narrow tracks.
Satellites have grown in reliability and precision, improving understanding of our planet’s rapidly changing frozen regions. Still, satellites have not been the only source of Earth observation. NASA, for instance, has supplemented satellite observations with fieldwork measurements such as SnowEx, and aerial surveys such as Operation IceBridge, which bridged the gap between the ICESat and ICESat-2 missions. Through it all, NSIDC has managed and shared data on behalf of funding agencies, namely NASA, NOAA, and the US NSF.
Teaching old maps new tricks
Working with satellite observations initially meant adapting existing tools not wholly suited to the task. Reflecting on satellite image processing in 1978, Arthur Cracknell of the University of Dundee recalled, “In those days photographic images were generated in Dundee on old photofacsimile machines salvaged from newspaper offices … [T]ransparent sheets with (curved) grids of latitude and longitude … were placed on top of the photographic paper or negative film while it was being exposed.”
Decades of technological advancement means satellite imagery is often provided in grid format today. Converting satellite observations of a round planet onto a flat grid involves tradeoffs and decisions, though, because there is no perfect method. NSIDC began innovating in the early 1990s with the popular Equal-Area Scalable Earth (EASE) Grids map projections, to improve representation of the polar regions.
Declassification, digitization, preservation, and rescue
NSIDC has provided a home and acted as a distribution hub for newly acquired satellite observations, but NSIDC has done more than that.
NSIDC has, on multiple occasions, rescued records that might otherwise be lost, such as Nimbus observations made before the continuous polar-orbiting satellite record. NSIDC has also preserved historical films, including Good Days on the Trail, 1938-1942, and International Geophysical Year, 1957-1958 Drifting Station Alpha Documentary. Film footage comprises just part of what NSIDC has preserved in the Arctic Ice Dynamics Joint Experiment (AIDJEX) collection, resulting from an American-Canadian Arctic project in the 1970s.
Some data rescues were facilitated by geopolitical change. During the Cold War, Eastern and Western Bloc nations considered the possibility that the Arctic region could become a theater of warfare. So, they collected libraries full of data about the frozen north, including observations gathered by submarines beneath Arctic sea ice. Starting in the 1990s, the United States and Russia cooperated to declassify and share observations of weather, climate, ocean circulation, and sea ice, in the form of Environmental Working Group (EWG) Atlases.
Ensuring historical records remain available to future generations sometimes requires putting old records into new formats.
As a cryospheric library, NSIDC stored more than books and journals. It also held a collection of glacier photographs, taken from the ground, from the air, and from space. NSIDC stored more than 20,000 photographic prints, and an additional 100,000 photographs on microfilm. The photographic prints were beautiful—an archive of glacier change over time. The prints were also fragile, and could only be viewed onsite, requiring interested viewers to travel to Colorado. In 2002, NSIDC began working with the NOAA Climate Database Modernization Program (CDMP). The result is the Glacier Photograph Collection, an online, searchable database of historic glacier photographs, some dating back to the nineteenth century.
Indigenous perspectives
Throughout the satellite era and well before that, some of the keenest insights on the Arctic have come from people who live there, and whose ancestors lived there. NSIDC through the Exchange for Local Observations and Knowledge of the Arctic (ELOKA) program has helped preserve Indigenous Knowledge with observation hubs, digital atlases, and websites while working with communities to ensure their data sovereignty.
The US National Science Foundation has funded the ELOKA program and other projects like the Navigating the New Arctic Community Office (NNA-CO), aimed at mitigating threats associated with rapid Arctic warming.
The cooperative efforts strive to foster collaboration and consultation with the aim of preserving and sharing local observations and knowledge of the Arctic. Indigenous perspectives have become a part of NOAA’s annual Arctic Report Card.
How computing and data storage technologies have advanced
Advancements in satellite technology and local observing networks would have been far less useful without corresponding advancements in computing, data processing, and storage.
In the mid-1960s, Intel co-founder Gordon Moore observed that transistors were shrinking in size and growing in number at a predictable rate. He predicted that the number of transistors on a computer chip would continue to double roughly every two years. The prediction became known as Moore’s Law.
In this Moore’s Law graph, the horizontal (time) axis is linear, but the vertical (transistor) axis is logarithmic. If the vertical axis were linear, this graph could run up the side of a skyscraper.
Growth in computing power was accompanied by dramatic declines in the cost of storing data. In 1976, storing a terabyte of data cost tens of thousands of dollars. Increasing demand from artificial intelligence operations has recently raised computer component prices, but even so, storage for a terabyte or more can be had for less than $50 today.
Falling data-storage prices translated into rising data-storage capacity. As satellites, aerial surveys, field expeditions, and local observation networks observed more, NSIDC could take in and share more data.
First, however, NSIDC needed supporting contracts.
Although NSIDC started in 1976, it did not get its current name until 1982. That year, NOAA established NSIDC as part of the Cooperative Institute for Research in Environmental Sciences (CIRES). NASA established its first contract with NSIDC the next year, to archive Scanning Multichannel Microwave Radiometer (SMMR) passive microwave sea ice data from the Nimbus-7 satellite. A decade after that, NSIDC became a NASA Distributed Active Archive Center (DAAC) in 1993, to manage cryospheric and related data for NASA’s Earth Observing System. In addition to SMMR, NSIDC began to manage and distribute data from many other satellite sensors. (See Our History for more.)
How data ingest has grown at NSIDC
Before NSIDC can distribute data on behalf of NASA or any other party, it must first ingest that data. NSIDC’s data ingest has not grown as dramatically as Moore’s Law predicted for transistors, but it has certainly increased.
NSIDC’s total archive volume passed the one-petabyte milestone in June 2019. NSIDC’s archive volume for NASA Earth science data sets stewarded by the DAAC crossed the one-petabyte mark in October 2019. NASA data sets accounting for the greatest growth in NSIDC data archives include NASA missions ICESat-2/ATLAS, VIIRS, SMAP, and Operation IceBridge.
“I remember it felt like a big deal when we passed the one-petabyte mark in data ingest,” said NSIDC technical services manager Daniel Crumly “but we quickly shot past that, especially when we started ingesting ICESat-2 data.”
Data holdings at NSIDC grew due to technological advancement—satellite sensors able to observe more and NSIDC able to take in and manage more data. NSIDC began stewarding quantities of data unimaginable when the data center started 50 years ago. Continued advancements meant that eventually NASA Earth science data sets moved into the NASA Earthdata cloud. NSIDC still distributes and supports data sets as a NASA DAAC.
As of September 2026, NSIDC hosts over 1,480 data sets, funded by NASA, NOAA, US NSF, and others.
Web surfing changed (not quite) everything
In NSIDC’s earliest days, data requests might arrive via the US Postal Service. Incomplete requests would have to be clarified through follow-up phone calls or correspondence. That would change, but not immediately.
Between late 1989 and late 1990, computer scientist Tim Berners-Lee developed the technology behind the World Wide Web. NSIDC launched its first website in 1994 and migrated to NSIDC.org several years later. The website’s look and feel soon evolved even more.
Over time, the site added educational content, scientific analyses, interactive applications allowing users to track changes, news and features, and functionality for data access.
NSIDC.org underwent periodic updates in structure and design, but the most comprehensive overhaul began in January 2020. “When we redesigned and organized the website back in 2020, we were dealing with over 20,000 pages of content that had accumulated over two decades,” recalled senior user engagement specialist Leslie Goldman, who led the effort. That overhaul concluded in July 2022, resulting in more logical design and greater consistency of user experience across programs and projects.
From a certain standpoint, NSIDC.org simply is the National Snow and Ice Data Center. The website is the data center’s face to the world, the portal to expertise about snow and ice, the means of sharing latest developments, and the way to find and use data. “One thing I love about our website is how it really demonstrates what makes NSIDC unique—that partnership between data stewardship and scientific research,” Goldman added.
From August 1, 2025, through July 31, 2026, NSIDC.org served more than 5 million pageviews. A significant portion of NSIDC traffic is focused on scientific data set access.
Making the website a useful portal to data took years of effort on NSIDC’s part, as well as changes in technology. The ease of access common today was a long time coming. Early Internet access still imposed major limitations. Dial-up connections made large files slow to download, and image-heavy or technologically demanding webpages could be impractical for many users.
NSIDC’s website made it easier for many users to contact the data center and request data, but not necessarily easier for NSIDC to distribute data. Requesting a big data set was one thing; downloading that data set at 1990s’ dial-up-modem speed was another. Before high-bandwidth Internet access was widespread, NSIDC had to provide users with an alternative to devoting hours of their time and telephone access to downloads.
Data distribution
Remember CDs?
In NSIDC’s earliest days, big data sets had to be relayed on big wheels of magnetic tape. By the early 1990s, NSIDC had switched to compact disc (CD) format. CDs were certainly less cumbersome than magnetic tape, but not without challenges.
Retired NSIDC senior associate scientist Mary Jo Brodzik recalled the early days of Equal-Area Scalable Earth (EASE) Grid data distribution. “For the original EASE-Grid data, we knew that it was so large that the entire time series for Northern Hemisphere would require many CDs, and I was seriously concerned about all that plastic. So, I went on a hunt for better packaging, and I found the vendor that made the soft-pack sleeves with the light cardboard covers. I made my pitch to the DAAC to distribute the EASE-Grid data this way—cheaper, lighter weight to ship, less space on the user’s storage shelf, more environmentally friendly—and we were off to the races.”
NSIDC programs and projects lead Donna Scott remembered how, as a User Services representative in the early 2000s, she spent hours packaging and mailing CDs. Some were for data distribution; others were for educational materials, such as When the Weather is Uggianaqtuq, which shared Indigenous perspectives on a rapidly changing Arctic.
Better bandwidth eases data downloads
Luckily for many scientific data users, growing sizes of data sets coincided with increasing bandwidth. Much of NSIDC’s efforts in recent decades have been to make data findable and downloadable via NSIDC.org. NSIDC user services lead Lisa Booker said, “Data sets are getting larger, and support is more about helping users manage large data. As NASA moves into the cloud, more user support will possibly be technical support.” One development Booker welcomes, as someone who did her share of mailing CDs, is improved online access. “More data are going into always-accessible archives. In earlier years, NSIDC Operations had to stage most of the data. That’s rare now.”
“Users are attempting more technical workflows,” Booker observed. “Still, we aim to make data easier to use for more users.”
Beyond making data easier to use, NSIDC has provided more context and scientific analysis on what is happening in the cryosphere.
Sharing scientific insights
In 2005, the Arctic September sea ice minimum was the lowest extent yet observed in the satellite record. NSIDC scientists began anticipating in June that a record-low minimum might merit a press release. NSIDC worked with NASA and the University of Washington on a joint announcement. On the day of the planned release, however, NASA experienced a delay. At the direction of a NASA scientist, NSIDC went forward with the minimum announcement.
“Whether or not it was NASA’s intention, that made NSIDC the go-to place for sea ice news,” said senior research scientist and DAAC scientist Walt Meier.
After the 2005 Arctic sea ice minimum pushed NSIDC to the forefront of sea ice news, NSIDC got even more proactive and, with support from NASA, launched its Arctic Sea Ice News & Analysis (now named Sea Ice Today) subsite in 2006. Before long, Sea Ice Today expanded its scope to include Antarctic sea ice, as well as freely available statistics spreadsheets and interactive tools.
Today, the analysis posts and data tools under the Sea Ice Today umbrella consistently account for the plurality of web traffic to NSIDC.org. The subsite’s success prompted other analysis subsites at NSIDC.
Greenland Today (now named Ice Sheets Today) launched in 2013, CIRES senior research scientist Ted Scambos, a regular contributor to Sea Ice Today, led the effort with a team of international scientists, starting a year after the Greenland Ice Sheet experienced record melt. Karl Rittger, a research associate with the Institute of Arctic and Alpine Research (INSTAAR), worked with NSIDC to launch Snow Today in 2019. Like Sea Ice Today, Ice Sheets Today and Snow Today come with their own suites of data visualization tools.
Another plus comes from the interactive tools on the analyses subsites that let users equipped with only web browsers visualize what is happening in Earth’s frozen regions. In 2012, some NSIDC software developers found the perfect chance to innovate.
Our killer apps
“I want to do something like Google Finance but for sea ice,” software developer Matt Savoie declared in 2012. Savoie was tossing around ideas with his software-developing colleagues Kevin Beam and Luis Lopez.
Beam had just joined NSIDC. “I had never worked in a science environment before,” he said. He, Savoie, Lopez, and all the other developers were preparing for an upcoming hackathon, a three-day event in which everybody tried to innovate and make something amazing.
Lopez suggested making something interactive. “I made the suggestion that it would be cool if users could click on the curve and get the sea ice extent for that day, making the chart more dynamic,” he recalled. “Kevin implemented that idea a few weeks later!”
The timing was right for a fresh round of innovation.
A decade earlier, NOAA@NSIDC had launched the Sea Ice Index, offering daily and monthly map views, and comparisons of concentrations, extents, and trends. “The Sea Ice Index put easily accessible products in users’ hands and became the basis for other products,” said general project manager Ann Windnagel. “It’s used within NSIDC and outside NSIDC, including the Arctic Report Card.”
Sea Ice Index maps, which had originally been monthly, had become available for daily values in 2012. The code underlying them had just been rewritten and updated. Savoie and Beam put together the first iteration of one of NSIDC’s most popular interactive tools: Charctic. “We got the first version up pretty fast. Then we made the argument of ‘Let’s put some money into this,’” said Savoie.
Users can choose which years to display, time of year to focus on, and hemisphere to show. Making Charctic work meant thinking about the big picture and the details, such as how to handle leap years. The interactive tool has undergone continued refinement since 2012. Meanwhile, Charctic-based visualizations have been published many times outside NSIDC, both for Arctic and Antarctic sea ice. “Seeing images I created in The New York Times is pretty awesome,” Savoie said.
Just as Sea Ice Today inspired other analyses subsites at NSIDC, Charctic inspired other visualization tools, such as the interactive Greenland melt map, and derived visualizations have also appeared outside NSIDC.
NOAA@NSIDC’s Multisensor Analyzed Sea Ice Extent - Northern Hemisphere (MASIE-NH) is another interactive tool that makes user visualization easy. MASIE answers the question, “Where is the sea ice edge right now?”
“Answering that question is important to entities operating in the Arctic, because the ice edge determines where ship passage is—and is not—possible,” explained retired NOAA@NSIDC program manager Florence Fetterer. MASIE was developed in partnership with the US National Ice Center. The partnership makes the ice center’s highly accurate operational data available to a wide community of researchers.
As for Beam, his software development did not conclude with Charctic. Years later, he was still hard at work on a NASA project to reduce barriers to finding and working with elevation data. The result was OpenAltimetry, which lets users browse and download data gathered by NASA’s ICESat/GLAS and ICESat-2/ATLAS platforms. As NSIDC’s DAAC manager Amanda Leon said, “OpenAltimetry exemplifies what NSIDC has done throughout its history: bringing together expertise in science, data, technology, and user needs to make complex Earth science data more accessible and useful.”
Led by NSIDC’s deputy lead scientist Twila Moon, QGreenland is an international project designed to work with QGIS open-source software. It has received funding from the US NSF, but also has editorial and coordinating boards in Greenland and Denmark. It lets users explore dozens of data layers across many different topics, from the ice sheet to ocean and infrastructure to landscape. Users can examine Greenland, including the ice sheet, coastal regions, and nearby ocean regions. In fact, some datasets even span the full Arctic.
All these successes came from NSIDC’s culture of innovation but also collaboration. “There is a special synergy at NSIDC,” Donna Scott remarked, “not just between science and data, but also between our data programs. NOAA feeds Sea Ice Today, but NASA DAAC data feed NOAA data.”
Reflecting on NSIDC’s first “modern” interactive tool, Charctic, Beam said, “I wanted to make more interactive visualizations, and Charctic was the first of those.” He also pointed to the value of making the data directly accessible. “You can explore it for yourself,” he said. “It’s all right there.”
Future plans and reflections
Kevin Beam, Luis Lopez, and Matt Savoie hope to finesse Charctic further: to make it responsive so it can function better on all screen sizes, to make it easier for users to select from the near-50-year archive of sea ice observations, and to let others embed the tool in their own webpages.
Leslie Goldman is pleased with what the NSIDC.org website has accomplished so far. “We have a comprehensive data catalog of cryosphere and cryosphere-related data products. We make the data more accessible through easy-to-consume data graphics, scientific analyses, and help articles. And we provide foundational content and articles about what the cryosphere is and why it matters,” she said.
Lisa Booker hopes to grow NSIDC’s user base even further. “We’re focusing more on operational data, for instance, how snow affects water capacity. I want to put more data into the hands of decision makers. I also want to reach beyond the traditional cryospheric researcher,” she said. Booker has also initiated a more integrated approach to training and outreach, incorporating efforts from User Services, Technical Documentation, and Communications groups at NSIDC.
Beyond a small library of published papers, NSIDC scientists have served as authors and editors for the annual Arctic Report Card and the Bulletin of the American Meteorological Association’s annual State of the Climate. These contributions have occurred regularly over decades. Exceptional dedication to NSIDC’s mission spreads well beyond the data center’s science team. Since 2007, CIRES Outstanding Performance Awards have been awarded to NSIDC employees 41 times.
In Mark Serreze’s office—on the same shelf as his data-storage artifacts of microfiche, magnetic tape, and big floppy disks—is a Covid-protection kit from COP26, the United Nations Climate Change Conference he attended in November 2021. “NSIDC has endured a pandemic,” Serreze pointed out. “No matter what has come our way, we’ve continued to do good work. No matter what happens 50 years from now, 100 years from now, people will remember that NSIDC has been on the right side of history.”