Eos, Transactions, American Geophysical Union Volume 95
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2014 AGU Fall Meeting Session Proposals Now Open! Visit fallmeeting.agu.org. News: NOAA Seeks to Make Its Data More Usable, p. 95 Forum: Linking Belowground Knowledge Across Scales, p. 96 Meeting: Sharing Resources for Aleutian Arc Research, p. 97 Meeting: Environmental Change in Northwestern Canada, p. 98 Research Spotlight: Subarctic Lake Desiccation, Magma Conduit Clog, p. 100 VOLUME 95 NUMBER 11 18 MARCH 2014 The Newest Oldest Data From NEWS Seasat’s Synthetic Aperture Radar A new suite of digital synthetic aperture The products were derived from data col- NASA’s Proposed Budget Sees Small Dip, radar (SAR) imagery, featuring historic views lected by Seasat, NASA’s first dedicated of Earth’s oceans, sea ice, volcanoes, for- oceanographic satellite, which launched Emphasizes Innovation and Autonomy in Space ests, glaciers, and more, was made available more than 35 years ago. Data from this mis- NASA’s proposed federal budget for fis- in science and technology, improve life on in its entirety for the first time by the Alaska sion are the earliest orbital SAR imagery cal year (FY) 2015, released on 4 March, Earth and protect our home planet, while Satellite Facility (ASF) in midsummer 2013. ever gathered. Other sensors carried on includes new plans to send a probe to Jupi- creating good paying jobs and strengthening board include a radar altimeter to measure ter’s icy moon Europa, a ramp up in fund- the American economy,” he said. spacecraft height above the ocean surface, ing for a mission to redirect an asteroid into However, proposed cuts, particularly to a scatterometer to measure wind speed and near-Earth orbit, funds to extend the life of education—which would drop nearly 24% direction, and a passive microwave radiome- the International Space Station (ISS) by at to $88.9 million compared to the FY 2014 ter to measure sea surface temperature. least a decade, and plans to return to the enacted budget—would force those reliant Although it suffered a catastrophic power United States the capability to launch astro- on eliminated funds to look for alternative failure in its fourth month of operation, in nauts into space, among other highlights. sources. 100 days, Seasat collected more informa- At $17.46 billion, NASA’s proposed FY 2015 tion about the oceans—its original focus— budget would see a small dip in funding com- than had been acquired in the previous 100 NASA’s FY 2015 Budget for Science pared to its FY 2014 enacted budget, a reduc- years of shipboard research. As a result, tion of about 1%. Cuts to NASA’s budget for About $179 million—roughly 3.5%—is to ASF’s suite of SAR products from the mis- science, exploration, and education encom- be trimmed from NASA’s Science Mission sion, available to users under NASA’s open- pass the bulk of the reductions (see Table 1). Directorate in the FY 2015 proposed budget access data policy, will help fill information “This budget keeps us on the same steady compared to the amount set for FY 2014. This gaps in cryospheric, geomorphological, and path we have been following—a stepping- would bring the Science Mission Director- environmental time series—data useful to a stone approach to send humans to Mars in ate’s funding stream to nearly $4.97 billion. range of scientific disciplines. the 2030s,” said NASA administrator Charles Within this cut, Earth science, planetary Mission Background Bolden at a 4 March teleconference. “This science, and astrophysics would lose some budget ensures that the United States will funding, although heliophysics would get a remain the world’s leader in space explo- slight boost (see Table 1). “Given the finan- With the launch of its Seasat mission on ration and scientific discovery for years to cial situation for the nation, a $5 billion sci- 28 June 1978, NASA undertook a historic come.” ence budget for Science Mission Directorate task: to demonstrate the feasibility of orbital If the proposed budget is enacted, it provides a balanced approach for us to sup- remote sensing for global ocean observa- would reaffirm the administration’s commit- port our number one effort, which is to pro- tions. In addition to the radar altimeter, ment that NASA be a catalyst for social and vide pathways to Mars,” Bolden said. scatterometer, and microwave radiometer, economic growth, Bolden added. Through it, this platform hosted an L band SAR sensor “we’ll continue to build on U.S. preeminence cont. on page 94 that collected imagery with a resolution of News 25 meters, obtained in 100- kilometer- wide swaths covering much of North America, Table 1. NASA’s Fiscal Year (FY) 2015 Proposed Budget Compared With the FY 2014 northern Europe, and the adjacent seas [Jor- Enacted Budget dan, 1980; Ford et al., 1980]. Percent Seasat’s SAR data collected by the sen- Proposed Change sor allowed scientists to create images and FY 2014 FY 2015 Percent OGSIb with OGSI detect surface waves, internal waves, the Program Enacteda Proposeda Change Additionsa Additions Gulf Stream system, the California Cur- rent, the North Pacific subtropical front, Science $5151.2 $4972.0 −3.5% $187.3 +0.2% and other coastal phenomena [Fu and Holt, Earth Science $1826.0 $1770.3 −3.1% 1982]. More than 100 passes were recorded over the Beaufort Sea, providing insight into Planetary Science $1345.0 $1280.3 −4.8% major morphological features, structural Astrophysics $668.0 $607.3 −9.1% changes, and drift motion of sea ice. Even with the power failure on 10 October of the James Webb Space $658.2 $645.4 −1.9% launch year, Seasat succeeded in its primary Telescope goal of taking oceanography into space. Heliophysics $654.0 $668.9 +2.3% During operation, Seasat utilized two basic orbital configurations at an inclina- Aeronautics $566.0 $551.1 −2.6% $43.9 +5.1% tion of 108°. The initial observational phase Space Technology $576.0 $705.5 +22.5% $100.0 +39.8% was a 17-day repeat cycle. On 8 September, the satellite was maneuvered into an exact Human Exploration $7891.2 $7881.4 −0.1% $450.6 +5.6% Fig. 1. Synthetic aperture radar (SAR) image 3-day repeat [Pounder, 1980]. Years later, Operations from Seasat of extensive shoals off Nantucket these repeat- pass data enabled scientists to Exploration Systems $3115.2 $2784.4 −10.6% Island and internal waves in the coastal pioneer the interferometric SAR technique, waters off Cape Cod, Massachusetts, obtained Development which provides a means to measure precise 27 August 1978. The Alaska Satellite Facility deformation from earthquakes and volca- Commercial $696.0 $848.3 +21.9% has recently processed and made available for Spaceflight the first time the complete SAR catalog from noes, for example [Gabriel et al., 1989; Zeb- ker et al., 1992; Zebker and Goldstein, 1986]. Seasat, NASA’s first dedicated oceanographic Exploration Research $302.0 $343.4 +13.7% mission, which operated between 26 June and and Development 10 October 1978. Seasat cont. on page 94 (HRPb and AESb) Space Operations $3778.0 $3905.4 +3.4% $100.6 +6.0% (ISSb and Space and Flight Support) Education $116.6 $88.9 −23.8% $10.0 −15.2% Cross-Agency Support $2793.0 $2778.6 −0.5% Construction, $515.0 $446.1 −13.4% $93.7 +4.8% Environmental Compliance, and Restoration Inspector General $37.5 37.0 −1.3% Total $17,646.5 $17,460.6 −1.1% $885.5 +4.0% aIn millions. b OGSI, Opportunity, Growth and Security Initiative; HRP, Human Research Program; AES, Advanced Exploration Systems; ISS, International Space Station. 93 EOS VOLUME 95 NUMBER 11 18 MARCH 2014 Seasat at https:// www .asf . alaska .edu/ seasat/. Over- cont. from page 93 views of Seasat can be found at http://www .jpl .nasa .gov/ multimedia/ seasat/ intro .html and http://www .nasa .gov/ vision/ earth/ In addition to oceanography, sea ice newly created coverage maps favorably lookingatearth/ Seasat _25 .html. motion tracking, and interferometry, the match historical coverage maps obtained Seasat SAR has key applicability for the fol- from NASA’s Jet Propulsion Laboratory (JPL), Acknowledgments TRANSACTIONS lowing types of studies: showing that most of the data were success- AMERICAN GEOPHYSICAL UNION • Images from Seasat SAR can be com- fully recovered. ASF thanks Paul Rosen at the Jet Propul- The Newspaper of the Earth and Space Sciences pared with mosaics of North America from sion Laboratory, California Institute of Tech- the Japanese Earth Resources Satellite 1 Current Seasat Products Status nology, whose guidance was invaluable to Editors ( JERS-1), collected in 1997, and the more the success of this data rescue project. Christina M. S. Cohen: California Institute recent Advanced Land Observing System-1 Although nearly all of the original SAR of Technology, Pasadena, Calif., USA; cohen@ Phased Array type L-band Synthetic Aper- data collected were processed optically References srl.caltech.edu ture Radar ( PALSAR), collected from 2006 to onto 70-millimeter filmstrips, only an esti- José D. Fuentes: Department of Meteorology, 2011. Such comparisons can help scientists mated 20% of Seasat data were ever digitally Ford, J. P., et al. (1980), Seasat views North Amer- Pennsylvania State University, University Park, detect land and boreal forest cover changes processed [Wu et al., 1982; Pravdo et al., ica, the Caribbean, and western Europe with Pa., USA; [email protected] through time. 1983]. In the 1980s, JPL’s technology was imaging radar, JPL Publ., 80-67, 361–370. Fu, L.-L., and B. Holt (1982), Seasat views oceans Wendy S. Gordon: University of Texas at Aus- • The seven orbit cycles of 3-day repeat able to digitally process one image a day.