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DigitalGlobe acquired crowdsourced intelligence pioneer Tomnod. Tomnod has been at the forefront of innovation in the growing field of crowdsourcing of earth observation imagery analysis, combining their unique and novel algorithms with deep GIS and imagery knowledge.

DigitalGlobe will continue offering Tomnod’s rapid information capture and validation services directly to customers. In addition, information gained by the service will increasingly act as a key data source for its in-house analytics teams, enabling them to provide more accurate insight and analysis to our customers faster.

The Tomnod team now has a new home at DigitalGlobe’s headquarters in Longmont, Colorado. DigitalGlobe believes that this is only the beginning of the potential for crowdsourced insight with exciting times ahead.

Internet: www.digitalglobeblog.com/2013/04/08/tomnod

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… with key optical components manufactured by Optical Surfaces Ltd., has helped Surrey Satellite Technology Ltd. (SSTL) win the 2012 Sir Arthur Clarke award for “Best Space Activity – Industry / project”. The prestigious awards, held by the British Interplanetary Society since 2005, recognizes notable contributions to the U.K. space sector.

NigeriaSat-2 is a 300kg class earth observation satellite manufactured by Surrey Satellite Technology Ltd (SSTL) for the Nigerian space agency (NASRDA). Benefiting from a high performance camera with optical components manufactured by Optical Surfaces Ltd., the satellite has been able to capture stunning 2.5m resolution images enabling detailed analysis of ground structures, aircraft and vehicles.

NigeriaSat-2 carries two imagers: A 2.5m resolution panchromatic and a 5m resolution multispectral with a swath width of 20 kilometres. Using proprietary production techniques, Optical Surfaces’ skilled craftsmen produced the 385mm light-weighted primary mirror, and other optics in the Cassegrain camera, with a surface accuracy of lambda/20 p-v that has enabled the high resolution images taken by the satellite.

Optical Surfaces Ltd has produced optical components and systems for more than 45 years and is now accepted as one of Europe’s leading manufacturers of high-precision optics for satellite deployment and astronomical research. The company’s ISO 9001-2008 approved manufacturing workshops and test facilities are deep underground in a series of tunnels excavated in solid chalk where temperature remains constant and vibration is practically non-existent. With such stable conditions testing, particularly with long path lengths, becomes quantifiable and reliable. Working with these natural advantages is a highly skilled team of craftsmen with a commitment to excellence in both product quality and customer service.

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Over the period March 22-24, 2013, northern and western regions of Ukraine experienced a snowfall equal to the monthly norm. The amount of snow and rising temperatures significantly increased the risk of potential floods.

The state of emergency was declared in Kiev and its neighboring regions by local authorities due to the storm and high flood risk. According to the resolution no. 58922/59/1-11 from 12 February 2013, the Cabinet of Ministers of Ukraine requires all local authorities to take all measures to be prepared for the floods.

UN-SPIDER’s Regional Support Office in Ukraine made a request to NASA to acquire images from the EO-1 satellite over the Kyiv region. The image was taken on March 29, 2013 at 07:59UTC, and was made available at about 11:25UTC, thus ensuring fast access and delivery of the satellite data. The image and products were delivered to the State Space Agency of Ukraine (SSAU) and local authorities responsible for dealing with the emergency.

Read more: UN-SPIDER RSO Ukraine

Source UN-Spider

The “Charter Geographic Tool” was developed by the Charter member CNES (French National Centre for Space Studies) in order to establish a comprehensive record of all images acquired by the Charter members in response to Charter activations, as the international mechanism reports in its latest newsletter.

Over and above the utility of such a record as an internal tool to the Charter, the main user requirement driving the development came from actors across the disaster management cycle to know where image data had been acquired during a given activation.

Since the creation of the International Charter „Space and Major Disasters? in 2000, images have been acquired by around 20 different Earth Observation satellites. Of this, over 4000 metadata files have been ingested in the catalogue by the Charter agencies.

The Charter Geographic Tool consists of three main components:

  • An image metadata catalogue based on PostgreSQL
    A FTP site which manages the harvesting of the metadata files uploaded by the Charter agencies
  • A web interface based on the mapshup framework. This user-friendly interface allows to search and browse the metadata catalogue by activation, date and hazard type.

The tool is accessible online

Source UN-Spider

(March 20). The PlanetObserver team is happy to announce the release of PlanetDEM 30, a new Digital Elevation Model (DEM) covering the entire Earth at 30-meter resolution, offering accurate, homogeneous and voidfree data.

PlanetDEM 30 is a fusion of 30-meter ASTER Global DEM v2.0 and PlanetDEM 90, PlanetObserver high quality 90-meter global DEM product. Further to an extensive R&D programme, PlanetObserver has developed exclusive data fusion processes. Based on this proprietary technology, PlanetObserver has produced PlanetDEM 30, a 100% global product, totally free of ASTER GDEM residual anomalies and artifacts that highly affected overall data quality.

Used as a major source to correct and enhance ASTER GDEM data, PlanetDEM 90 is a unique global elevation product developed by PlanetObserver. Based on the combination of 90-meter SRTM (Shuttle Radar Topography Mission) data v4.1 corrected and completed with cartographic data, this highly accurate product has already been acquired by major players of the spatial and defence industry.

PlanetDEM 30 overall accuracy is a major asset for all applications, even the most sensitive. This worldwide 3D reference dataset is ideal for Defence, orthorectification, mapping, weather systems, terrain modelling applications, energy exploration and geology, just to name a few sectors.

PlanetDEM 30 broadens PlanetDEM product suite, PlanetObserver range of elevation data.

About PlanetObserver
PlanetObserver offers a full range of value-added geospatial products : global imagery mosaics in natural colours with a unique visual quality and truly global high quality Digital Elevation Models. All products are developed internally, backed up by PlanetObserver’s know-how in geospatial data processing and over 20 years of technological expertise.
PlanetObserver imagery and terrain products are perfect for numerous commercial, military and consumer applications, ranging from web-mapping to 3D visualization and simulation solutions, flight simulation, cartographic mapping to audio-visual production.
Contact
www.planetobserver.com

Under the umbrella of the thirty-third session of the United Nations Inter-Agency Meeting (IAM) on Outer Space Activities this week in Geneva, UNOOSA and the United Nations Office for Disaster Reduction (UNISDR) organized the 10th Open Informal Session entitled: “Space and Disaster Risk Reduction: Planning for Resilient human settlements.”

The session was inaugurated by Ms. Margareta Wahlström, Special Representative of the Secretary-General (SRSG) for Disaster Risk Reduction; Mr. Niklas Hedman, Chief of the Committee Policy and Legal Affairs Section of the United Nations Office for Outer Space Affairs and Ms. Helena Molin-Valdes, Coordinator of the “Making Cities Resilient Campaign” of the United Nations International Strategy for Disaster Reduction.

The session, open to delegations of Member States and other organizations of the United Nations system, included two panels:

  • Towards resilient cities: A wider use of geospatial data in urban planning;
  • Mainstreaming space technology in land use planning and rural development strategies for effective disaster management.

The panels included keynote presentations by the Information Technology Agreement Committee on Underground Space of the International Tunneling and Underground Space Association (ITA-AITES) and the Global Facility for Disaster Reduction and Recovery of the World Bank (GFDRR). These were complemented with comments and presentations by representatives of UN-HABITAT, UNISDR, UNITAR-UNOSAT, UNOOSA/UN-SPIDER, EC-COPERNICUS and the University of Eastern Paris, Marne-la-Vallee.

The session provided an opportunity for representatives of Diplomatic Missions in Geneva to become aware of the usefulness of space-based applications in disaster-risk reduction and for all participants to discuss ways to promote the use of such applications in countries exposed to natural hazards, including through efforts within the “Making Cities Resilient”-campaign of UNISDR and the upcoming session of the Global Platform for Disaster Risk Reduction which will take place on 19-23 May 2013 in Geneva, Switzerland.

All background documents and presentations are available online on the website of the United Nations Coordination of Outer Space Activities (“UNCOSA:http://www.uncosa.unvienna.org/uncosa/en/iamos/index.html).

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(Source EURISY, March 2013) A mix of satellite images, in-situ measurements and air quality models are used to detect air pollutants and guide city authorities in improving traffic management to reduce emissions.

The city

Antwerp is the capital and the largest municipality of the Antwerp province in Flanders, Belgium. The Urban Development department of the city, depending from the Flemish Environmental Agency, is the entity in charge of monitoring air and noise pollution at the local level.

The challenge

Antwerp is particularly affected by air pollution generated by the eight-lane motorway passing near the city centre, its important seaport, as well as by the presence of the second petrochemical industry worldwide. Moreover, the high buildings located in the city centre create street canyons where noise and pollutants are especially concentrated.

Every year, the Flemish Environmental Agency produces reports on the concentration levels of different pollutants (PM10, PM2.5, NO2, BC) present in city hotspots. Such reports, based on measurements at the street level, inform on the situation in previous years. However, they do not include the forecasts which the Municipality needs to devise adequate future traffic management plans to reduce emissions and noise.

The satellite solution

In 2010, the Municipality contracted VITO, a research institution, for an air pollution assessment study based on a combination of satellite images, ground sensors and air quality models. On the basis of this data, combined with the noise pollution maps of the Municipality, “black-spots” were identified, where air and noise pollution are highest. Not surprisingly, these black spots were found to occur in areas with the highest traffic concentration.

Thanks to the combination of satellite imagery and air quality models, which are able to capture relevant information on street topography, the new maps did not only provide assessments on current noise and air pollution, but also allowed city managers to make predictions about the impact of different traffic scenarios on air quality in the future.

The result

The traffic scenario assessment system, created in 2010, allowed city managers to make predictions about the impact of different traffic scenarios on air quality in the future and to priorities areas where intervention to curb traffic was most needed.

As a result, the Municipality decided to make changes in traffic circulation and speed limits, to increase the number of eco-friendly buses, to increase supervision and regulation of industrial emissions and to create a low emission zone in the centre of Antwerp.

In the future, the municipality aims at updating these maps every five years.

“The traffic scenario assessment system based on satellite and ground measurements enables us to take better-informed decisions to improve traffic management in Antwerp”, Jan Bel, City of Antwerp, Urban Development, Energy & Environment.

Source EURISY

Ball Aerospace and Technologies Corp. has begun integration for WorldView-3, the next generation commercial remote-sensing satellite being built for DigitalGlobe, a leading global provider of high-resolution earth imagery solutions.

The third satellite in a series to employ the Ball Commercial Platform (BCP) 5000, WorldView-3 is slated for launch in mid-2014. For more than a decade Ball Aerospace has partnered with DigitalGlobe to deliver increasingly advanced imaging satellites, including WorldView-2 in 2009, WorldView-1 in 2007, and QuickBird in 2001.

“Our experience building spacecraft for DigitalGlobe has allowed for quick progress on WorldView-3,” said Cary Ludtke, vice president and general manager of Ball’s Operational Space business unit.

“WorldView-3 will be a highly capable spacecraft based on a low risk design with proven results. We’re eager for it to join DigitalGlobe’s growing constellation.”

Currently the integration of the control moment gyroscopes (CMGs) and the propulsion module is underway in anticipation of the ITT Exelis imaging sensor delivery in mid-2013. Following successful sensor integration and checkout, environmental testing of the completed satellite is scheduled to begin in this fall.

WorldView-3 will offer 31 centimeter resolution panchromatic, 1.24 meter resolution eight-band multispectral and 3.72 meter resolution eight-band Short Wave Infrared (SWIR) imagery.

U.S. government restrictions require DigitalGlobe’s imagery provided to non-U.S. government customers be limited to no more than 50 centimeters panchromatic, 2.0 meter multispectral or, 7.5 meter SWIR.

WorldView-3 builds upon the WorldView-2 and WorldView-1 technology by carrying forward the satellite’s advanced CMGs. The CMGs reorient a satellite over a desired collection area in 4-5 seconds, compared to 30-45 seconds needed for traditional reaction wheels.

As WorldView-3 joins the modern fleet of WorldView-class satellites, DigitalGlobe will have the largest high resolution satellite imagery collection capacity in the industry.

In addition, the range of customer applications enabled by the DigitalGlobe constellation and overall value DigitalGlobe can provide to customers is greatly expanded by issuance of a license from the National Oceanic and Atmospheric Administration to collect eight-band short-wave infrared imagery.

Jeff Culwell, vice president of DigitalGlobe’s data business line notes this will allow WorldView-3 the ability to sense both the visible spectrum as well as deeper into the infrared spectrum that provides a rich dataset to precisely identify different manmade and natural materials.

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(08 April By Matteo Luccio, Copyright Sensors & Systems). Research scientists continue to add to our understanding of Earth systems, thanks to the global earth observation capacity. Waleed Abdalati, associate professor of Geography at the University of Colorado, Boulder, director of the Earth Science & Observation Center, a Fellow at the Cooperative Institute for Research in Environmental Sciences, and former NASA Chief Scientist, has a perspective that encompasses the capacity, coming capabilities, and ongoing challenges. Sensors & Systems (S&S) special correspondent Matteo Luccio spoke with Abdalati about the inspiration that is provided through Earth observation, the need to balance satellite-based sensors with in-situ observations, as well as his research work studying ice and climate change.

S&S: Who or what inspired you to go into science? Why aerospace engineering science?

Abdalati: The Apollo program inspired me, from the time I was a young kid. I used to pretend that I was one of the Apollo 11 astronauts. There was just a magic, an inspiration in there that stayed with me through grade school, into college, and onward. When Apollo 16 or 17 went up, I was in the second grade and I remember telling my teacher, “I don’t understand. The rocket is moving really fast and the moon is moving really fast and so you have to aim the rocket someplace where the moon isn’t, so that they get there at the same time.”

That was my second grade mind. “The moon has to be there by the time the rocket gets there. How do they do that?” I asked. She said, “They use all kinds of math to figure it out.” I remember thinking, “Math… I am going to learn some math!” I thought it was really cool. From that moment on, I was always fascinated by trajectories, by the movement of objects, orbital mechanics, and that kind of stuff. So, it really was the Apollo era that planted the seeds that stayed with me throughout my career.

S&S: Hopefully, the Curiosity mission will do the same for another generation.

Abdalati: I sure hope so! There’s a real magic to it.

S&S: How does your training in geography guide your work?

Abdalati: I worked as an engineer for a little while and at some point I just became more interested in what the satellites were seeing rather than the design and development of them. I worked on Earth-observing satellites early on and I thought, man, there is just a real beauty on the Earth down there that is so important to understand that I became equally as inspired in trying to understand how the Earth works. Frankly, it was serendipitous: I took a class with a person who later became my advisor who did work in the Arctic and it just looked beautiful. So, it was the perfect marriage of my aerospace engineering interest, using satellites to study the Earth, my interest and appreciation for the Earth system in all its beauty, and the intrigue and adventure of going to the Arctic and studying glaciers and ice sheets.

S&S: What have been the key advances or milestones in Earth observation in the last 20 years?

Abdalati: In a general sense, it’s been just the real recognition of the Earth as a system and the interconnectedness of the various elements. Things like dust storms in the Sahara affecting hurricanes in the Eastern United States. How those two relate in a very specific sense. My own area of research, realizing that glaciers and ice sheets—things that we used to think take hundreds or thousands of years to respond to changes in today’s climate—actually respond in minutes, hours, days, months, weeks, years, centuries, and millennia, on all time scales, but the fact that there is an instantaneous effect of today’s climate on these very old, thick, slow-moving ice sheets was a major revelation in my own discipline.

Being able to look inside hurricanes and tropical storms and understand their three-dimensional structure, where the rain is falling, why it is falling, what the vertical temperature structure looks like can help us get better at predicting their trajectories and their intensity. It’s hard to pick a few, but I’ll grab a couple more. Another one is the spatial characteristics of sea level rise. Or even not just the secular trend of sea level rise, but weekly or monthly types of variability when things like El Niño set in or we transition to La Niña. The spatial character of the ocean topography tells us a lot about the physics related to ocean circulation, the energy characteristics in the ocean, and that’s just something that you cannot adequately sample with buoys or ships. The oceans are huge. Historically, we measure sea level rise using tide gauges on the coast, but those measurements are complicated by the fact that the land in which they are planted is moving in relation to the ocean. So, you get a relative sea level. From satellites, we get a terrestrial reference frame that allows us to observe absolute sea level rise.

More than 20 years ago, it was satellites that observed the decrease in the ozone in Antarctica, the ozone hole, and ultimately led to the adoption of the Montreal Protocol and to means of correcting that. And then, finally, the shrinking Arctic sea ice is a very visual illustration of how our planet is changing and this is an area that is far removed from most people’s everyday lives, and yet it is very important to the Earth system. Still, we don’t think about it that much because we don’t see it, we don’t live it, we don’t breath it, but when the satellites show the rate at which the ice is shrinking and the spatial character and combine that with the fact that our models have difficulty capturing that rate, those are huge advances.

S&S: What have been some of the key turning points in the technology aboard the satellites?

Abdalati: I’ll go way back, to 1960. Simply being able to observe the Earth from space with the TIROS [Television Infrared Observation Satellite Program] mission. One of the really big technology advances has been interferometric synthetic aperture radar [InSAR]. The ability to measure small relative displacements over large areas, in ways we just can’t do on the ground with the same degree of comprehensive coverage, has just been tremendously powerful. To inform us about Earth deformation, uplift and subsidence in certain areas associated with all kinds of geophysical processes, such as the movement of glaciers. InSAR has been tremendously powerful.

The technology associated with GRACE, the Gravity Recovery and Climate Experiment, is also tremendously powerful. By observing the change in distance between a pair of satellites we can infer the gravitational characteristics of the Earth below the satellites and thus make assessments about the movements of mass on the Earth so that we can detect the depletion of aquifers or the filling or draining of reservoirs, the changes in ice sheets, and the movements of water masses in the ocean. Then there are the standard things like getting high resolution visible imagery. When people can look at their Earth in this way, we see it very differently.

Finally, in my own specific area of research, lidar technology has provided and will continue to provide great advances in our understanding of the Earth system. The idea that we can accurately map the topography of ice and land surfaces, or the optical characteristics of the atmosphere, using lasers with such precision is truly remarkable. This capability is enabling major science advances by improving our understanding of the structural characteristics of land, ice, and vegetation, as well as the aerosols and radiative characteristics of the atmosphere.

S&S: What will be the next big advance in terms of payload?

Abdalati: That’s a tough call, because there are so many things in the works that are at different technical readiness levels. I think that the soil moisture, active and passive (SMAP) mission, to measure the water content in the soil and its implications for ecosystem health and water availability for humans on Earth, will be a very substantial advance. I also think the next ICESat mission, ICESat-2, is a different kind of laser remote sensing. It will provide detail on ice topography and the topography in other areas, potentially vegetation structure. That, I think, will be a big advance over what we’ve done to date. Wide-swath ocean altimetry, where, rather than a pencil beam of ocean topography, we get a swath that gives us more and better information on spatial structure. There are many things in the works. I tend to focus my own research on Earth surface processes. I am not being fair to the atmospheric science community, but there are, no doubt, big things coming down the pipe there.

S&S: What are the most critical environmental variables that can be measured best (or only) from space?

Abdalati: What determines those are the spatial scales over which meaningful processes occur and their accessibility. So, ocean circulation is certainly huge. The fact that we can look at the wind vectors in the ocean from space to tell us which way surface winds are blowing and the fact that we can look at the salinity in the oceans and the ocean topography to understand the ocean circulation itself. Large scale atmospheric phenomena, such as big hurricanes and major tropical storms, are another. We have had great success flying airplanes into storms and measuring their structure, but to really get a comprehensive picture of the space-based view is incredibly powerful. You need both. You can’t do it all from space, but you can’t do it without the space-based view. The last one I will mention (although there are many) is ice cover. Greenland, Antarctica, the Arctic sea ice, the Antarctic sea ice. These are large-scale processes that are very difficult to observe any other way.

S&S: What in situ measurement by ground-based sensor networks can best complement the work of space-based Earth observation?

Abdalati: Certainly, the ocean is a big challenge and ocean buoys with sensors that capture temperature, wind, radiation, anything else we can measure, are critical. The buoy networks are essential. Using spectrometers to understand the spectral characteristics of various surface types and phenomena, so that we can interpret our space-based observations is tremendously important. Air-borne measurements of atmospheric chemistry and structure in storms and other large-scale dynamic processes are essential to help us interpret what we are seeing from space—as ground validation, if you will.

Basically, anything we can measure from the ground is a big help, because, one, it is another set of data points and, two, it is another step in robust calibration of our space-based observations. They help us understand and add meaning to what we are observing from space. Look at the range of things we’ve got flying. It becomes kind of apparent what we need to do on the ground in terms of validation. We want to have similar observing tools on the ground as we have in space, for calibration.

Then, there’s the other piece: the information that we can’t get from space. I’ll come back to oceans: for the most part, we can only observe the surface, and we rely on our understanding of the physical processes to interpret what we see on the surface and infer what it tells us about what is happening below the surface. We observe surface expression of subsurface processes. So, definitely, observations on the ground or in the sea of subsurface characteristics: what is making the ocean do what it is doing? The deployment of expendable bathythermographs, or XBTs, and various other devices, is certainly an important part of a robust observing system. On the ground, meteorological towers, stations, and the like, are essential, because different things happen as you get closer to the ground.

Often, from space we are looking at column information: we are looking at the integrated effects from the surface of the Earth to the top of the atmosphere and only with some exceptions do we examine the stratification of the atmosphere and get vertical information. So, anything that helps us validate our observations and bring insight on the vertical aspect of what we’re seeing, what’s happening in the z dimension, is absolutely critical.

S&S: How is the mix of EO satellites changing — in terms of missions, technology, public vs. private, nationality, etc.?

Abdalati: One way the mix is changing is that we don’t have a flagship mission in our future—things like the Terra, Aqua, and Aura missions, which have multiple sensors for coincident observation. The missions, now and in the foreseeable future, are more targeted. They have very specific objectives that are a little more focused and we rely on models and observations from other sensors to do the integration. Whereas with flagship missions in the Earth-Observing System some of that integration occurred by coincident observation. We have the A-Train, we have multi-sensor missions. The transition is toward single-sensor missions or, maybe, dual-sensor missions with a single primary focus.

In terms of who is doing what, there is certainly much more commercial capability out there. If you just look at the high-resolution commercial imagery and compare that to the Landsat observations, which have been a staple for scientific research over the years, that’s testimony of what private industry is capable of doing. Industry, however, will always be driven by the market, by a business model that has to close, otherwise those businesses will not be successful. There are some things for which the business model won’t close. This is partly why we have Landsat 8 and the Landsat series: because, while people may pay a good price for really high resolution data of certain areas of interest, there isn’t quite the same market for lower-resolution, consistent, global-scale coverage, yet it is necessary for science, to understand the behavior of the planet. So, I think there is a place for business, there is a place for government entities, for the kinds of research activities that NASA has historically supported.

There are also other new niches, such as small satellites that industry is pioneering that may be able to fill some of the gaps that we are starting to see. But, we have developed the Earth-Observing System, which was robust and entirely government-supported, targeted at understanding how and why our Earth is changing and what the implications of those changes would be. The systems in place now, or coming down the road, are a little more focused, looking at new things in new ways, looking at old things in new ways, and in a few cases looking at old things in old ways.

There is plenty of room for innovation and ingenuity, to fill the gap that the current budget constraints are forcing us to have. The number of satellites and the capabilities in Earth observing is something that we, as a nation, should take pride in. At the same time, it is not the grand vision that was initiated years ago, because budget reality forced choices and reductions, so it is a bit of a different landscape. Launch costs will affect that as well. We had the tragic loss of two very important missions and it’s difficult to recover from that.

S&S: What are some of the types of sensors that do not currently have much of a commercial reason for existing but are still important for science? Perhaps InSAR (interferometric synthetic aperture radar)?

Abdalati: There are certainly commercial applications of InSAR. It isn’t clear yet whether they are sufficiently robust to warrant private industry taking over developing a SAR mission. So far, we have not seen it emerge, so my feeling is that it is not. Another one is something like GRACE, the Gravity Recovery and Climate Experiment. That’s tremendously powerful for understanding our world. Who is going to pay for it? I can’t really think of anyone. If we look at something like the depletion of aquifers, whoever cares about their one system of reservoirs or their water tables will invest in local measurements. They aren’t thinking about it at a global scale. I see GRACE as something that is great for the world, but is not going to grab one company or one investor to say, “Yeah, this is a real money maker.”

There is not really a business case for things like passive microwave satellite data, the things we use to monitor the sea ice cover, in some cases the snow over land and a few other things, yet it is important for understanding weather, climate, and the Earth as a system. So, there are some things that are really important that nobody is really going to pay for except the sponsors of scientific research who are the most immediate beneficiaries of the information that they provide.

S&S: Why the trend toward single-sensor, single-focus missions?

Abdalati: It’s due to a couple of things. Some of it is risk, you spread the risk over multiple launches, because the launch has become a real issue. Another is complexity: it becomes very hard and complex to integrate several instruments on one platform, each with different observing requirements and targeted observations can be optimized for the purpose for which they were designed.

S&S: From what you’ve learned so far, how and why is the Earth’s ice cover changing and what do those changes mean for life on Earth?

Abdalati: The Earth’s ice is growing in some places and shrinking in others, but the amount of shrinking is by far greater than the amount of growing. This has impacts for Earth in several ways. One is that if you look at ice sheets—in Greenland and Antarctica, certainly in West Antarctica—the loss of ice, and the loss of glacier ice in other parts of the world, is contributing to sea level rise. Oceans are going up and the keys to the rate at which they go up and how high they will ultimately rise are locked up in the ice. So, sea level rise is one big implication for life on Earth.

Sea ice and Arctic and Antarctic ice cover play important roles. One is to help keep the planet cool, by reflecting a lot of the incoming sunlight. White ice is reflective, so it prevents the sunlight from being absorbed in the Arctic and Antarctic. As that ice starts to melt, particularly sea ice, and exposes dark water underneath, more and more energy gets absorbed by the polar oceans. Second, the presence of ice affects ocean and atmospheric circulation. There is a very big barrier to energy transfer between the ocean and the atmosphere that affects the surface circulation of both and, ultimately, the climate. Third, when sea ice forms, it rejects salt into the sea water and that salt causes density increases at the upper ocean. So, you now have cold, salty water that sinks and spreads along the bottom of the ocean and affects ocean circulation in that way—quite simply, the displacement characteristics from the density changes associated with the formation of the ice.

S&S: What is the most important thing you’ve discovered about sea ice, ice sheets, and/or glaciers that the public does not know or does not understand?

Abdalati: I think the public is becoming increasingly aware, because ice is binary: it’s there or it’s not. So, there are some very visually compelling images and information about the ice cover. We’ve discovered that they are changing faster than we ever thought possible. The movie “Chasing Ice” consists of a series of time-lapse photographs of different glaciers throughout the Earth and chronicles the retreat of the ice cover of the glacier ice. It is has been so successful in part because it is just plain visual. You see ice, then you see it go away. The same is true with satellite images. The public’s appreciation for its disappearance or sensitivity to climate has gone up, but I think what we’ve discovered most recently and what may still not be fully appreciated is how fast these changes can occur. We’ve seen glaciers flow faster than we used to think was ever possible. The sea ice is shrinking faster than what all of the models that we’ve used for climate prediction—there are about 16—predicted. It’s this rate of change that I think is something I would hope people would appreciate more.

The other is the role of ice in the climate under which human civilization has evolved. I don’t think people fully appreciate that humans have never known a time without Arctic sea ice cover in the summer. It’s always been there and the resulting ocean circulation has always been with us. So, I don’t know that people fully appreciate the potential for significant changes associated with the changes in the ice.

S&S: What do you hope most to learn from ICESat-II?

Abdalati: I hope to learn the amount by which ice sheets and sea ice are changing, because it will enable us to learn about sea ice thickness. Beyond that, however, I also hope that we acquire tremendous insights into the mechanisms driving those changes. The three things that affect the growth and shrinkage of ice sheets are how much snow accumulates, how much melts and runs off, and how much flows into the sea (the iceberg calving). Each of those mechanisms has a topographic signature that, I hope, we will be able to decipher from the ICESat-II data.

S&S: How do you measure the thickness of the ice sheets over land?

Abdalati: We use ice-penetrating radar. Sometimes, we pull the radar on a sled, behind a snowmobile. If we want to do detailed surveys in very local areas, sometime we put these radar on aircraft and we just fly transects to measure the thickness of the ice.

S&S: I didn’t think that radar could penetrate as deep as the ice can be…

Abdalati: It depends on the wave length of the radar—the longer the wave length, the greater its penetration capability—and on properties of the ice. Cold ice is quite a bit more transparent to radar than warm ice. Wet ice is opaque; you can’t really penetrate the water. Under cold conditions, like in the middle of Antarctica or the middle of the Greenland ice sheet, you can go through more than two miles of ice because this is really cold ice and it is ideal for ice-penetrating radar. In coastal areas, where the ice is warmer and where the bedrock geometry is more complicated, it gets harder. In the case of the bedrock geometry, it’s not that the radar cannot penetrate the ice, but that it gets harder to decipher the bottom from reflections off the side of channels through which the ice is flowing.

S&S: What is your current understanding of the key variables and interactions affecting ice flow, melt, and deformation?

Abdalati: As a glacier flows into the sea, it often becomes afloat. In Antarctica and parts of Greenland that floating ice exhibits a buttressing effect, it holds back the glacier. The glacier wants to flow faster, but the floating ice acts like a plug, a barrier to the flow. As oceans and the atmosphere have warmed and the floating ice has melted, many of the glaciers are speeding up, because this buttressing effect is reduced or eliminated. When we observed it—particularly when the Larsen B ice shelf collapsed and the glaciers feeding it flushed their ice into the sea—that was a major advance in our understanding. It was theoretically developed decades earlier, but never really widely accepted until we observed it.

S&S: Is there a direct, linear relationship between the melting of ice sheets and sea levels?

Abdalati: The relationship between the melting of ice sheets and rising sea levels is approximately linear. However, the relationship between discharge—like the speeding up of the glaciers—and sea level rise is non-linear. You have this pent-up energy that’s been there for centuries as the glacier has tried to flow into this ice shelf and its flow has been restricted. Once that barrier is removed, like the collapse of the Larsen B ice shelf, which can be rapid, the response is also rapid. That’s the non-linear response.

Source

The Canadian Space Agency (CSA) has announced its oldest Earth observation satellite Radarsat-1 is unlikely to recover fully from an anomaly experienced on March 29. After the incident, the satellite was put into “safe mode” while the agency investigates what happened.

Radarsat-1, launched in 1995, has already been operating for 12 years more than it expected five-year lifespan. It is equipped with a synthetic aperture radar, which allows the satellite to capture images of the Earth through clouds, smoke and haze. The data and images collected by Radarsat-1 have been used to track the effects of global climate change and for resource and disaster management by both government and commercial customers. CSA has halted all orders for new imagery, but continues to provide archived data.

The space agency assured that the problems with Radarsat-1 do not have an impact on the country’s security since its successor Radarsat-2, launched in 2007, is working properly. Unlike Radarsat-1, this satellite is not owned and operated by the Canadian government but by MacDonald Dettwiler and Associates (MDA). Through an agreement with the government, MDA received partial funding for Radarsat-2’s manufacturing and launch. In exchange the company provides data to the government as long as the satellite is functional.

CSA is currently working on a new generation of Radarsat satellites set for launch in 2018.

Source

CBC

Ottawa