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From People to Pixels: Integrating Data Across the NASA DAACs

A Blog post by Lindsey M. Harriman (SGT, Inc. Contractor to USGS EROS Center/LP DAAC) and Alex de Sherbinin (WDS Scientific Committee member)

Socioeconomic and Earth Sciences researchers in search of pertinent data can now reap the benefits of a recent collaboration between two Regular Members of the ICSU World Data System.

Today, our planet supports about 7.6 billion people, with a projected increase to nearly 10 billion by 2050, and more than 11 billion by 2100. These 7.6 billion people are using land and water resources to meet their basic needs. As the population increases, their use of, and their impact on, Earth’s resources is going to change. Researchers who study the dynamics between such human–land interactions and their changes over time will look at a range of variables, such as surface temperature, vegetation health, forest cover extent, and change in land cover and habitat, as well as impacts of natural disasters, and climate trends and extremes.

Research questions that often ask about such dynamics include:

  • What is the proximity between populated areas and fire occurrences over time?
  • What is the correlation between the increase of population and land surface temperature in urban areas?
  • How has population affected land-cover change and vegetation growth over time in urban sprawl areas?
  • How will land-cover changes affect flood and drought risk around rural and urban settlements?

To answer these types of questions, researchers need to integrate census data with Earth observation data, including data collected by NASA’s Earth Science Division Operating Missions. Recently, two NASA Distributed Active Archive Centers (DAACs)—the Land Processes DAAC (LP DAAC; WDS Regular Member) and the Socioeconomic Data and Applications Center (SEDAC; WDS Regular Member)—collaborated to make that integration much easier. LP DAAC and SEDAC worked together to provide access to georeferenced population data alongside land remote sensing data in the Application for Extracting and Exploring Analysis Ready Samples (AppEEARS). SEDAC’s Gridded Population of the World version 4 (GPWv4) aggregates census data from around the world into a globally consistent grid with 30 arc-second resolution (1 kilometer at the equator) for population density and counts. Soon researchers will also have access to age and sex distribution grids. LP DAAC disseminates land remote sensing data collected by several NASA missions—including from the popular Moderate Resolution Imaging Spectroradiometer (MODIS) sensor onboard Terra and Aqua—and provides access to a selection of these datasets through AppEEARS.







Figure 1. Daily land surface temperature in Kelvin (K) and population trend, 2010–2017 for rural and urban points in North Carolina (based on MODIS MOD11A1 daily 1-km data and GPWv4, UN-Adjusted)
(a) Farm northwest of Nashville, North Carolina, USA. The red pin represents the location 36°N, 78°W. Image: Google Maps. Time series plots: output from AppEEARS.
(b) Suburban area of Charlotte, North Carolina, USA, experiencing rapid population growth. The red pin represents the approximate location 35°N, 81°W). Image: Google Maps. Time series plots: output from AppEEARS.

Figure 1 provides examples of time series plots of population growth and daily land surface temperature using the Point Sample function in AppEEARS. Users can interact with these visualizations within the application and also download the data values in comma separated value format.

Additionally, LP DAAC has collaborated with a third DAAC, the National Snow and Ice Data Center DAAC (NSIDC DAAC; WDS Regular Member), to provide MODIS snow-cover data from its archive for access through AppEEARS as an additional variable describing land dimension. SEDAC, LP DAAC, and NSIDC DAAC are all part of NASA’s Earth Observing System Data and Information System, and through their collaborations, AppEEARS now provides access to more than 100 data products from the three data centers in a single place, at no cost to the user. Many possible combinations of data can be extracted from AppEEARS for use in analyses of the dynamics between populations and ecosystems over time.

AppEEARS also provides benefits during the data preparation process. When performing a sample request, users drastically reduce the amount of data they ultimately need to download to perform their analysis. AppEEARS enables users to subset data based on geographic and temporal parameters, as well as by specific data layer. Since users can reformat the data and reproject within the application, the amount of post-processing required is reduced. Furthermore, AppEEARS not only provides data values, but also quality data values and their descriptions, when applicable. Lastly, users can visualize plots of the data values (point sample) or summary statistics (area samples) from the sample request within the application.

The collaboration around AppEEARS represents an initial step away from the idea that users need to download large amounts of data for local filtering, processing, integration, and analysis, and moves towards a model where analysis-ready data can be more immediately accessed. Coordinated tools and application development on the substantial holdings of all 12 DAACs is an important strategic direction for NASA’s Earth Science Data and Information System Project (WDS Network Member).

So, what’s your use case for AppEEARS?

Additional information about the DAACs mentioned above can be found here:

Have questions about AppEEARS? Email: .

Finding Paleoclimate Data via the World Data Service for Paleoclimatology Just Got Easier

A Blog post by Wendy S. Gross, and Eugene R. Wahl, (World Data Service for Paleoclimatology)

The World Data Service for Paleoclimatology (WDS Regular Member;, housed at the National Oceanic and Atmospheric Administration's National Centers for Environmental Information, provides data and information to understand natural climate variability and future climate change.

Paleoclimatology is the study of ancient climates, prior to the widespread availability of instrumental records. Paleoclimatologists study several different types of environmental proxy evidence to understand what the Earth’s past climate was like and why.

Paleoclimate proxies and reconstructions used to understand the Earth’s past climate.

Finding the paleoclimate data you need among the greater than thirteen thousand studies, covering the globe and freely available online, just got easier. With our new web service, you can search for data across a wide range of proxy types and climate reconstructions. The new service integrates all of the capabilities of our previous search mechanisms, allowing them to be used together in new and powerful ways, and in conjunction with logical operators.

WDS-Paleo3.pngGeographic coverage of World Data Service for Paleoclimatology data.

There are multiple ways to search for relevant data: input a search term into the general search text box, select a data type from the menu, narrow your selections in the advanced search feature, or use all these capabilities together. The search automatically builds an application programming interface for you based on your search criteria that you can then reuse in the future. After inputting your search criteria, the results will be populated with all relevant studies, as well as providing an overview of the metadata that links to any additional data and information.

A new feature is a section of the site that hosts predefined searches paleoclimatology scientists have found most useful in the past. You'll be able to select one or multiple data types, such as ice cores or corals, from the list assembled by scientists, and the search will produce the most relevant and noteworthy studies related to that topic. In addition, the predefined searches page enables you to jointly query by location and data type. You’ll also be able to search through every study related to a specific data type, with user-friendly columns that allow you to easily sort through the studies.

Using the new web service can help you discover information on topics such as:
• Finding common years of great drought or wetness across specific regions
• Coral records related to El Niño occurrences
• Air temperature reconstructions

The World Data Service for Paleoclimatology archives and distributes data contributed by thousands of scientists around the world. We highly appreciate their long-lasting contributions of data submission, and our collaborations with them. To contact the World Data Service for Paleoclimatology, please email: .

Essential Climate Variables – Global Glacier Change Data Indicate Continued Strong Ice Losses in 2015 and 2016

Isabelle Gärtner-RoerA Blog post by Isabelle Gärtner-Roer (WDS Scientific Committee member)

Changes in glaciers provide some of the clearest evidence of climate change, and as such they constitute key indicators and unique demonstration objects of ongoing climate change. Beside this scientific aspect, glacier changes have an impact on local hazard situations, regional water cycles, and global sea level.

The Global Terrestrial Network for Glaciers (GTN-G) is the framework for the internationally coordinated monitoring of glaciers in support of the United Nations Framework Convention on Climate Change. Within GTN-G, the World Glacier Monitoring Service affiliated at the University of Zurich, Switzerland (WGMS, WDS Regular Member)—which celebrated its 30th anniversary last year—is responsible for the collection and documentation of glacier fluctuations such as annual mass balances and length changes.

Fig 1: Mean annual mass balance of reference glaciersFigure 1. Mean annual mass balance of reference glaciers.

Latest mass balance data of the hydrological period 2014/15 and preliminary estimates for 2015/16 indicate continued strong ice losses. In fact, after 2002/03, 2014/15 is the second most negative year since the beginning of the monitoring program at WGMS (as shown in Fig. 1 for glaciers with long, continuous measurement programmes; the so-called 'reference glaciers'). This value is negative despite most of the glaciers in Norway and Iceland, as well as the few that are monitored in New Zealand and Antarctica, showing positive balances in the corresponding year (see Table 3 on this page). Since 1999/00, WGMS has already documented four years with a global mean ice thickness loss of more than 1000 millimetre water equivalent (mm w.e.). These new data show a continuation in the global trend of strong ice losses over the past few decades, and bring the cumulative average thickness loss since 1980 of the reference glaciers to almost 20.000 mm w.e.

As a Regular Member of the ICSU World Data System, WGMS publishes glacier data in a standardized format and makes them freely available to scientists, policy makers, and the wider public. Access is provided online through the 'Fluctuations of Glaciers Browser' and the 'Glacier App', as well as being consolidated in the 'Global Glacier Change Bulletin'.

Fig 2: Training course on glacier mass balance in La Paz, Bolivia (Photo: M. Zemp)Figure 2. Training course on glacier mass balance in La Paz, Bolivia (Photo: M. Zemp)

Upcoming challenges in glacier monitoring are very much related to the disintegration and vanishing of glaciers. Some of the glaciers under monitoring programmes disintegrate into several parts, while others—such as the Lewis Glacier on Mount Kenya—completely disappear. These issues demand continuous adaptation of monitoring strategies on both a local and global level. This is one reason why WGMS organizes training courses for Principal Investigators who perform glacier measurements and deliver their glacier data to WGMS. The last training course was held in 2016, with participants from Latin America (Mexico, Colombia, Ecuador, Peru, Bolivia, Chile, and Argentina) joining who are involved in ongoing mass balance programmes in their region (see Fig. 2). These participants were trained in both fieldwork and data analysis by an international team of experts in glacier monitoring and capacity building.

Our work relies on the cooperation and help of many scientists and observers throughout the world. We highly appreciate their long-lasting contributions in collaboration with our National Correspondents coordinating the collection of data in their country for submission to WGMS.

Further information:

1. Latest mass balance data
2. Global Terrestrial Network for Glaciers
3. World Glacier Monitoring Service
4. Movie documentary of the 30-year jubilee of WGMS

WorldWideScience Alliance: An International Partnership to Improve Access to Scientific and Technical Information and Research Data HomepageA Blog post by Lorrie Apple Johnson (WorldWideScience Alliance Operating Agent)

The WorldWideScience Alliance is a strategic partnership between national and international libraries and data and information centres from around the world. The ICSU World Data System and the WorldWideScience Alliance share reciprocal Associate Memberships, and both organizations are committed to eliminating barriers associated with finding and sharing scientific and technical information, including scientific research data. The Alliance provides the governance structure for the global science gateway, (, which facilitates federated searching across over 100 scientific and technical databases from more than 70 countries. The WDS Data Portal is among the data collections searched by, along with 14 other resources focussed on data, Languagesand the Alliance is actively seeking new data resources and partners.

The federated search technology employed by offers users a number of distinct advantages, including the ability to perform a real-time, simultaneous search of multiple databases, some of which may not be indexed by typical search engines. Users receive a consolidated, relevance-ranked results list incorporating information in textual, multimedia, and scientific data formats. Multilingual translations capabilities are automatically performed in ten languages, which makes scholarly material, including scientific data, more accessible to a worldwide audience.

The ability to search data collections within also addresses many of the challenges associated with discoverability of research data. For example, unless a user is familiar with a particular data centre, or knows that a specific dataset exists, it can be difficult to identify and locate scientific data; especially those outside of the researcher’s own discipline or speciality. enables users to receive data results in a separate results tab, and upon selecting a specific result, users will be directed to the landing page at the originating source, which in turn makes the data accessible for viewing or downloading. The inclusion of data collections in, Data Search Resultsparticularly as part of the broader public access movement among government research funders in many countries, further expands access to Research and Development results during the full research lifecycle, and ultimately contributes to increased scientific collaboration and progress.

The WorldWideScience Alliance is eager to include new resources in, and feedback is always welcome.

For more information about and the Alliance, please visit

2016 SciDataCon-China: The Third China Scientific Data Conference

Guoqing LiA Blog post by Guoqing Li (WDS Scientific Committee member)

On 25–26 August of 2016—two weeks before SciDataCon 2016 took place in Denver, USA—the Third China Scientific Data Conference was held in Shanghai, China. As can be understood from its abbreviation of SciDataCon-China, this Chinese-speaking conference is the national-level platform for communication about scientific data; just as SciDataCon, hosted by ICSU’s World Data System (ICSU-WDS) and Committee on Data for Science and Technology (CODATA), is at the international level.

2016 SciDataCon-China was co-hosted by Fudan University, which houses the first Data Science Laboratory to be set up in China. Greater than 380 experts, scholars, and students from universities, institutes, companies, and governmental agencies gathered in the Zhangjiang Campus of Fudan University to attend in excess of 20 breakout sessions over the two days. Although the number of participants was slightly fewer than the 400 who attended the Second SciDataCon-China in 2015, oral reports significantly increased to more than 160 from around 100 last time, making it the leading scientific data conference in China.

Different from the Information Sciences approach, SciDataCon-China has kept a domain-oriented emphasis as a primary principle from its beginnings. Breakout sessions mostly served the multidisciplinary community, covering such diverse fields as Materials Science, Astronomy, Space Science, Geography, Ecology, Earth Observation Science, Marine Science, Smart Cities, Precision Medicine, and Agriculture, as well as the management, analysis, and visualization of scientific Big Data.

2016 SciDataCon-China

SciDataCon-China is not only a communication platform for domain scientists and information scientists, but also a dialogue platform for scientific communities and decision-makers. Consecutive sessions on data policy, funding policy, and large-grant programme management were jointly held by the Ministry of Science and Technology and the Chinese Academy of Sciences. An important conclusion of the conference was that the opening and sharing of scientific data should be supported mainly through national finances; in particular, because scientific data can help to accelerate the construction of national innovation capacity.

A session by WDS-China has been a regular and popular feature of each SciDataCon-China since its conception. On this occasion, greater than 40 experts from 7 Chinese WDS Members were at the WDS-China session alongside numerous attendees from local data centres. Discussions and reports focussed on the topics of the maintenance and future development of Chinese WDS Member Organizations, the sustainability of national scientific data centres, creating a uniform metadata service within WDS-China, the long-term preservation of published data, and so on.

Under the oversight of the WDS Scientific Committee, and supported by the WDS International Programme Office, WDS-China and WDS-Japan are now working together to realize the inaugural WDS Asia-Pacific Symposium: a regional communication platform for scientific data. Thus, there will be a seamless transition of WDS communications from the national, through the regional, to the international level.

SciDataCon-China is an annual event organized by the China National Committee of CODATA in cooperation with the WDS-China Coordinating Office and other partners. The First conference was held in January 2014 in Beijing, and the Second in August 2015 in Lanzhou. The next SciDataCon-China will take place during August 2017 in Kunming; co-hosted by the Kunming Institute of Botany, Chinese Academy of Sciences.

A New Challenge: Building Multidisciplinary Distributed Research Data Infrastructures – EPOS - European Plate Observing System

Aude ChambodutA Blog post by Aude Chambodut (WDS Scientific Committee member)

Researchers who specialize in a particular Earth Science discipline (seismology, geomagnetism, gravimetry, geochemistry, geology, etc.) cannot fully describe the history and crustal structure of a region of the globe using ONLY their specific research field. They often need to consult a large number of references and databases from other research domains. Interdisciplinary studies are still hampered by the necessity for researchers to document themselves effectively with many ‘external/foreign’ contributions, and to have colleagues in these fields who are willing to collaborate.

Of course, many efforts have been made to group datasets, mainly by discipline, and make them available to the greatest number in a trusted database. However, interdisciplinary approaches still remain a matter of exception. Good ideas are sometimes dismissed simply because of life: difficulty in easily finding a reliable data source understandable to a non-specialist, trouble in speaking the same language as the scientific colleague of the other discipline, lack of time,…

The greatest advances in Earth sciences were made using transdisciplinary collaborations. We say often that ‘the data noise of one proves to be useful information to another’ and vice versa. This is true even within the same discipline; indeed in geomagnetism: for one magnetic field measurement, the inner part interests the main-field modeller, while its ‘noise’ contains the ionospheric field studied by an ionospheric physicist.

Over the last decades, considerable advances in information technology have made an integrated approach possible, easing access to the tremendous amount of data and products available across the Earth Sciences and related fields. Large multidisciplinary projects are initiated to facilitate integrated use of data, data products, and tools from distributed research infrastructures for Solid-Earth science in Europe.

In this matter, EPOS—the European Plate Observing System1—is currently one of the most exciting under-development, long-term integration project in Europe. EPOS strategy is not to erase all that was previously done, but to integrate existing national or transnational structures (e.g., seismic and magnetic permanent monitoring networks, and analytical laboratories) and to develop a new interoperabillity layer that will be seen as a common interface.

Long-standing existing structures (National, European, or International services and data centres), together with newly developed databases (for less centralized/organized disciplines), will be virtually gathered into a central hub of which the key functions will be: an Application Programming Interface, a metadata catalogue, a system manager, and services that will enable data discovery, interactions with users, as well as access, download and integrate data2.

Data will be made available from the Solid-Earth Science disciplines that each community deals with, such as seismology, geomagnetism, geodesy, volcanology, geology and surface dynamics, analytical and experimental laboratory research, rock physics and petrology, and satellite information. Available data will be quality controlled according to the appropriate standards as defined by each of the disciplinary data providers.

For pre-existing entities, their visibility will be enhanced. For new structures, their creation will help the community to consolidate scattered data that are hidden and distribute them in a uniform database. For researchers in the Solid-Earth Sciences, EPOS will facilitate innovative cross-disciplinary approaches for a better understanding of the physical processes and the driving forces involved (a seismologist will get access to trusted magnetic anomaly maps; a gravimetrician will be able to use reliable strain rate maps from the Global Navigation Satellite System community to compare with their own results). From a societal point of view, EPOS will enable scientists to better inform governments and society on natural hazards, such as earthquakes, volcanic events, tsunamis, and major land movements. 

EPOS is in its implementation phase. By 2018, EPOS is expected to be a legal entity: the EPOS ERIC (European Research Infrastructure Consortium).

For more information see:
2. EPOS is a partner of RDA Europe, the European plug-in to the Research Data Alliance (