Спутник ФКИ. ICESat. [Редактировать]

ICESat, один из спутников НАСА предназначенный для дистанционного зондирования Земли, предназначался для проведения измерний объемов льда на планете, частиц и аэрозолей в атмосфере, измерения растительного покрова.  Он проработал 7 лет и был затоплен в феврале 2010 года после того как отказала полезная нагрузка и НАСА не смогло ее перезапустить. 

Дополнительные наименования

#НаименованияПоиск в новостяхПоиск в документах
1Ice, Cloud, and Land Elevation SatelliteНайтиНайти
227642НайтиНайти

Дополнительная классификация

#Наименования
1Тип оператора(владельца) - государственный
2Страна оператор(владелец) - США
3Страна производитель - США

Новостная лента[Найти информацию в новостях] [Найти информацию в документах]

#Новостная лента.
12003-07 - 2003-08. Один из трех бортовых лазеров отказалТэги: ICESat

Технические характеристики

#ХарактеристикаЗначение
1Масса, кг970
2Масса (полезная нагрузка), кг302
3Масса (платформа), кг580
4Масса (топливо), кг76
5Емкость запоминающего устройства (для научных данных), ГБит56
6Емкость запоминающего устройства (для телеметрии), мБит в секунду256
7Платформа 1xBCP-2000
8Мощность солнечных батарей (конец жизни), Вт1962
9Мощность (предоставляемая), Вт696
10Мощность (требуемая), Вт825
11Мощность (полезная нагрузка), Вт350
12Емкость (аккумулятора), ампер часов40
13Точность определения позиции, град<0.006
14Скорость работы полезной нагрузки, мБит в секунду40
15Точность контроля позиции, град<0.006
16Точность позиционирования, метра<<30

Характеристики орбиты

#ХарактеристикаЗначение
1САС, год7
2Дата (сведения с орбиты)2010-08-30

Пусковые характеристики

#ХарактеристикаЗначение
1Код NSSDC2003-002A

Экономические характеристики

#ХарактеристикаДата измеренияЗначение
1Оператор Космическое агентство США
2Производитель Ball Aerospace
3Производитель Ball Aerospace

Информация об удачном запуске

#ХарактеристикаЗначение
1Дата пуска2003-01-13 at 00:45:00 UTC
2Полезная нагрузка 1xICESat
3Полезная нагрузка 1xCHIPS
4Ракета-носитель 1xДельта 2

Найдено 1000 документов по запросу «ICESat». [Перейти к поиску]


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0.56/5
... of cloud fraction between the ICESat lidar and the ECMWF model... of cloud fraction between the ICESat lidar and the ECMWF model... System (GLAS) lidar on the ICESat satellite. In order to account... compared to the ICESat lidar. Lidar forward model and ICESat comparison is... of cloud fraction between the ICESat lidar and the ECMWF model..., Cloud and Land Elevation Satellite (ICESat; Zwally et al. 2002) is... variation of global cloud profiles. ICESat lidar data have been available... make a fair comparison between the ICESat lidar and the ECMWF model... model variables. Processing of the ICESat lidar signal is necessary to... of cloud fraction between the ICESat lidar and the ECMWF model... is the orbit altitude (m) of ICESat. The dimensionless extinction-to-backscatter... extinction coefficient is α (m −1 ). At the ICESat 532 nm wavelength, there is... model and then compared to ICESat data. b. Converting Model Variables to... of cloud fraction between the ICESat lidar and the ECMWF model... that would be measured by ICESat in (a) a 4-km-thick ice cloud... of cloud fraction between the ICESat lidar and the ECMWF model... µ rad 170 µ rad 75 m Table 1: ICESat characteristics relevant to this study... to compare this model to ICESat, should the values of effective... of cloud fraction between the ICESat lidar and the ECMWF model... October 2003, chosen as the ICESat latitude-altitude analysis showed cloud..., allowing a direct comparison between the ICESat lidar and the ECMWF model... time and space) to the ICESat track are extracted. The horizontal... available at 3-hour intervals. The ICESat track points are arranged into... the closest ECMWF data available. ICESat points between 00 UTC and... UTC model analysis, and the ICESat points between 0130 UTC and... the following day. Once the ICESat points have been grouped in... model profiles closest to the ICESat ground track are extracted, containing... of cloud fraction between the ICESat lidar and the ECMWF model... variables interpolated on to the ICESat height grid. i. Cloud Fraction Resampling... model with cloud fraction from ICESat, the cloud fraction data are... threshold (minimum detectable backscatter of ICESat, shown in in table 1) is... of cloud fraction between the ICESat lidar and the ECMWF model... of cloud fraction between the ICESat lidar and the ECMWF model... of cloud fraction between the ICESat lidar and the ECMWF model... −45 −40 0 Figure 4: Processing of ICESat lidar data for the same... m above the surface. b. Averaging of ICESat Backscatter Data To compare backscatter... model and backscatter from the ICESat lidar, ICESat profiles which correspond to... maintaining the ICESat vertical resolution. Figure 4 shows the processing of ICESat lidar... model grid selecting and averaging ICESat 5 Hz rays to the nearest... due to the grouping of ICESat 5 Hz (1.2 km) rays to individual... that corresponded to less than 5 ICESat 5 Hz rays (7 km of ground... km). The maximum distance between ICESat track and model grid points... 2i, with the number of ICESat profiles replacing the sub-columns... model. 4. Results Fifteen days of ICESat observations, from 30 September 2003... where the length of the ICESat track is over 9 million kilometers... than the sensitivity of the ICESat lidar. Cloud fraction is also... ice cloud falling beneath the ICESat sensitivity threshold. • In mid-latitudes... that are made; comparing the ICESat-derived cloud fraction directly with... substantially higher than with the ICESat observations. In particular, the mean... 2003 2359 UTC under the ICESat track. (b) Cloud fraction from the... and the cloud fraction resampled. (c) ICESat cloud fraction data for the... all the signal received at ICESat is purely noise. Frequency of... comparing the thick solid line (ICESat observations) with the thin solid... low, but agrees with the ICESat observations. • Similarly, the tropical frequency... km, but agrees with the ICESat observations otherwise. Frequency of occurrence... thick solid line indicates the ICESat lidar measurements, the thin solid... 20 Height (km) 0.3 0.2 0 Height (km) ICESat Lidar (a) Height (km) Height (km... 60 80 0 Figure 7: Comparison of ICESat lidar and the lidar forward... surface. (a) ICESat lidar mean cloud fraction; (b) ICESat lidar frequency of occurrence; (c) ICESat lidar... Height (km) 0.3 10 0 Height (km) ICESat Lidar (a) Height (km) Height (km... backscatter can drop beneath the ICESat sensitivity threshold, but β WP will... is underestimating the backscatter from ICESat above 10 km by a factor... model) to that derived from ICESat. Using a cloud fraction threshold of... 90 −6 −4 10 0 −6 10 10 −4 10 ICESat ECMWF ECMWF error bars Figure... present (bottom row) taken from ICESat and the ECMWF model over... less) cloud falling within the ICESat sensitivity threshold. Frequency of occurrence... model and observations from the ICESat lidar over a 15 day period... long-term measurements with the ICESat satellite. However, due to the... thin clouds over Europe using ICESat lidar spacebourne observations, Mon. Weather..., S. Palm, J. Spinhirne, and R. Thomas, 2002: ICESat’s laser measurements of polar ice...



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0.16/5
..., September 12-14, 2007, Finland ICESAT FULL WAVEFORM ALTIMETRY COMPARED TO... waveform; DTM; AHN; Laser altimetry; ICESat. ABSTRACT: Since 2003 the spaceborne..., Cloud and land Elevation Satellite (ICESat) has acquired a large world-wide... database allows us to compare ICESat to AHN elevation profiles with... allows us to determine improved ICESat profiles. Comparing the improved profiles..., Cloud and land Elevation Satellite (ICESat) was launched separated into vegetation... Normaal Amsterdams Peil) (RDNAP, 2003 ICESat has acquired a huge database of... full waveform as a result of ICESat GLA14 data to profiles derived.... As most improvement is The ICESat GLA14 elevation data are obtained... complex terrain, comparison results GLA01 ICESat full waveform data with the...−10−2003 ' "' Figure 1. Study area: ICESat ground tracks (magenta) displayed with... ICESat footprints filled with AHN points are shown. 2.2 Figure 2. Principal of ICESat... European reference system (Hazeu, 2003). 2.3 & 2.3.1 ICESat data overview: Among 15 GLAS... stored in the GLA05. This ICESAT/GLAS GLAS uses a laser altimeter... of AHN data A 70m-diameter ICESat footprint contains approximately 700 AHN... elevation profiles of AHN and ICESat data. To avoid effects of... of a laser altimeter vector, L, and a ICESat/GLAS geocentric vector, G, with respect... the orbit position of the ICESat satellite with respect to the... ICESat footprint ellipse. This mean elevation is then subtracted from the ICESat... difference. In this study, six ICESat tracks or six elevation profiles... 1 for an overview of the ICESat tracks. The differences over the... in Figure 3. For comparison between ICESat and AHN, both data sets... GLA14 footprint ellipses. Because the ICESat footprint has an approximate diameter... to a representative elevation point. For ICESat two profiles are determined, one... ICESat GLA14 data (red line), AHN data (black squared line) and ICESat... red box in Figure 1. • Many ICESat pulses of the 24-10...-11 Total In Figure 5, the ICESat GLA14 elevation is represented by... the ground elevation in the ICESat data (red circle). Finally the... 290 1588 Table 1. Number of ICESat waveforms used: F (Forest), U (Urban), B (Bare... missing AHN data. 4.2 4 Number of ICESat waveforms F U B W Total 72 158 456... used The waveforms from six ICESat tracks are assigned to different.... On average, 97% of the ICESat measurements to the ground were... elevation data and AHN (a) 0 the ICESat track of October 16, 2003... 3 shows the differences between the ICESat last mode or ‘ground elevation... bottom image shows that the ICESat ‘ground elevation’ profile (in cyan... the ICESat ‘mean elevation’ profile. It is also visible that the ICESat... AHN laser points within the ICESat footprint will result in a mean... that are considered, the ICESat ‘mean elevation’, the ICESat ‘ground elevation’ and... so large that the visible ICESat ground return is ignored by... in the third example the ICESat ground return is totally absent... the ICESat ‘ground elevation’ gives clearly a better value than the ICESat ‘mean... (black) precisely match to the ICESat raw full waveform (red) and... AHN ground points within the ICESat 70m footprint. The peak of...: Figure 7(c) shows a case where the ICESat waveform shows only one mode... this case the ICESat ‘mean elevation’ and the ICESat ‘ground elevation’ are... ICESat (GLA14) ICESat (GLA01) AHN Water Bare1313 1314 1315 1316 1317 1318 ICESat(GLA14) − AHN ICESat(GLA01) − AHN Fricker, H. A., Borsa..., K. and Bills, B., 2005. Assessment of ICESat performance at the salar de... Lindenbergh, R., 2006. Analysis of repeated ICESat full waveform data: methodology and... for the remaining differences between ICESat ground elevation’ profiles and the... directions: those footprints were the ICESat waveform shape match the shape... to assess the accuracy of ICESat georeferencing. On the other hand... improved. Harding, D. J. and Carabajal, C. C., 2005. ICESat waveform measurements of within-footprint...) and height differences (middle) of ICESat, GLA14 and GLA01-derived elevations... cases. At the bottom the ICESat footprints overlaid on a Google Earth... question. ICESat/GLAS Data at NSIDC, http://nsidc.org/data/icesat/faq... AHN, and two based on ICESat data. NASA provides height data... ICESat waveform. By considering the position of the last mode in ICESat... can be obtained from the ICESat data that is on average... deviation of ±1.1m. Zwally, J., 2002. ICESat’s laser measurements of polar ice... forest canopy block almost all ICESat laser energy. This gives one...



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0.25/5
... Cloud and Land Elevation Satellite (ICESat) carries a Geoscience Laser Altimetry System... principle . . . . . . . . . . . . . . . . . 36 4.2 Overview of the ICESat laser altimeter mission . . . . . . . . . . . . 37 4.2.1 Measurement... and Outlook . . . . . . . . . . . . . . . . . . . . . . . . . . 106 6 Validation of ICESat Elevations in Churchill, Manitoba 111... thickness from HEM measurements and ICESat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 7.3.2 7.4 Sensitivity analysis . . . . . . . . . . . . . . . . . . . . . . . . 162 Summary... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 4.1 Laser operational period for ICESat/GLAS since mission launch . . . 43... the total freeboard for 10 ICESat mission phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134 7.2 A summary of... of the thickness estimates . . . . . . . . . . . . . 163 A.1 ICESat GLAS-13 record . . . . . . . . . . . . . . . . . . . . . . . . . 190 xi... et al., 2005). . . . . . . . 4.2 33 38 ICESat measurement principle – GLAS measures the...). The ICESat position is determined from the GPS and ICESat orientation and.... . . . . . . . . . . . . . . . . . 66 4.11 The regression of ICESat elevation differences (∆h) and sea level... cycles during February-March 2003 ICESat mission phase. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 4.12 The... at each ICESat footprint – Spring 2004 epoch (ArcGICE study). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 6.1 ICESat footprints..., Hudson Bay. ©Google Maps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117 6.2 ICESat footprints (in red) and leveling... ICESat (blue) near Churchill. ICESat elevations after applying the tide-difference (between ICESat... freeboard during February-March 2006 ICESat phase . . . . . 140 7.5 Sea ice backscatter... Satellite (ICESat). ERS covered only up to 81.5◦ N/S, while ICESat, launched in 2003, provides coverage up to 86◦ N/S. Therefore, ICESat is... thickness estimation procedure? 7. How does ICESat elevations compare with field measurements... derived from ICESat. - In Chapter 4, the description of the ICESat sea ice... satellite missions such ICESat, and the upcoming missions ICESat-2 and Cryosat-2, cover... sea ice freeboard retrieval from ICESat are introduced. 4.1 Radar altimetry measurement... accuracy of ICESat over multiple surface types (Chapter 6). Applications Although, ICESat was... atmospheric aerosol distributions. Mission description ICESat was launched from the Vandenberg...). The ICESat position is determined from the GPS and ICESat orientation and... ICESat tracks and, therefore, this correction reduces those variances. 4.4.6 Snow depth ICESat... for assimilation. Chapter 6 Validation of ICESat Elevations in Churchill, Manitoba 6.1 Motivation... be carried out throughout the ICESat missions. ICESat, and upcoming altimetry missions... the ICESat instrument, but rather to assess the real differences between ICESat... such as ICESat, Jason 1 and 2, and upcoming missions Cryosat-2 and ICESat-2. 6.2 Validation... different ICESat epochs impacted the measured elevation accuracy and precision. The ICESat... and ICESat. Hence, the comparison between the precise leveling measurements and ICESat... compare the ICESat measurements with the field measurements. However, ICESat tracks from... of the ICESat track (i.e., only 20 or less ICESat footprints). The ICESat footprints... ICESat (blue) near Churchill. ICESat elevations after applying the tide-difference (between ICESat... and ICESat measurements were large in (i) topographically complex areas because ICESat did... provide more ICESat 131 footprints for comparison, as more ICESat epochs (and... between ICESat and survey measurements. But, a larger width of the predicted ICESat... from ICESat – Results The sea ice freeboard heights derived from ICESat laser... the ICESat-based thickness 161 Sea ice thickness distribution 0.25 HEM ICESat... from ICESat (blue) and HEM (red). distribution. This is because more ICESat... thickness classes were sampled by ICESat. 162 7.3.2 Sensitivity analysis A sensitivity analysis... from ICESat since 2003 (and, in the future, possibly Cryosat-2 and ICESat... G. Fotopoulos (2007), Assessment of SRTM, ICESat, and Survey Control Monument Elevations...–284. Carabajal, C. C., and D. J. Harding (2005), ICESat validation of SRTM C-band digital... DC. Harding, D. J., and C. C. Carabajal (2005), ICESat waveform measurements of within-footprint.../2000JC000469. Kwok, R., and G. F. Cunningham (2008), ICESat over Arctic sea ice: Estimation..., R., G. F. Cunningham, H. J. Zwally, and D. Yi (2006), ICESat over Arctic sea ice: Interpretation..., C. F., R. H. Thomas, W. B. Krabill, and S. S. Manizade (2005), ICESat range and mounting bias estimation..., J. P. DiMarzio, V. P. Suchdeo, and H. A. Fricker (2006), ICESat Antarctic elevation data: Preliminary precision... ICESat The procedure for deriving the sea ice freeboard heights from ICESat is explained in this section. 1. The ICESat GLAS-13...



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0.13/5
... © Author(s) 2016. CC Attribution 3.0 License. ICESat laser altimetry over small mountain... rough mountain terrain. Differences between ICESat GLAS elevations and reference elevation... ICESat acquisition period 2003–2008. We find spatially varying biases between ICESat... the method, rather than ICESat uncertainty. ICESat matches glacier size distribution of... thematic subsetting. Vertical offsets to ICESat elevations vary for different glaciers... Geosciences Union. 2130 D. Treichler and A. Kääb: ICESat laser altimetry over small mountain... such as the Himalayas. Subsequently, ICESat elevation measurements combined with the.../10/2129/2016/ D. Treichler and A. Kääb: ICESat laser altimetry over small mountain...., 2011; Andreassen et al., 2016). 2.2 ICESat ICESat GLAS was a single-beam spaceborne... analyses, the ICESat data set used was GLAS/ICESat L2 Global Land... and A. Kääb: ICESat laser altimetry over small mountain glaciers Methods ICESat data points... al. (2012) where differences between ICESat elevations and a reference DEM (hereafter... spatial coverage before complete ICESat failure.) Note that ICESat captures a signal of...-processing and filtering of ICESat data ICESat surface elevations (height above reference... and spatially co-registered with ICESat (see Sect. 3.2). Reference elevations for... land, and ∼ −2 m for ice samples (i.e. ICESat elevations are lower than reference... between DEM acquisition date and ICESat elevation measurements are included while.../10/2129/2016/ D. Treichler and A. Kääb: ICESat laser altimetry over small mountain.... The elevation corrections assessed include ICESat saturation elevation correction (attribute d_satElevCorr...–2146, 2016 2134 D. Treichler and A. Kääb: ICESat laser altimetry over small mountain... frequency Normalised frequency 0.16 dh ICESat - Kartverket DEM, uncorrected Samples on... ICESat sample overview Roughly 75 % of the nearly 170 000 ICESat footprints... appropriate. 4.2 Representativeness of ICESat glacier sample The entire ICESat glacier sample appears... glacierized surface in southern Norway, ICESat slightly oversamples east-facing glaciers.../10/2129/2016/ D. Treichler and A. Kääb: ICESat laser altimetry over small mountain... Figure 3. Representativeness of 2003–2008 ICESat autumn campaign samples in terms.../ 4.3 Error sources and corrections for ICESat and DEM elevations Elevation errors... of corrections available in the ICESat products. ICESat elevation corrections from effects..., 2129–2146, 2016 D. Treichler and A. Kääb: ICESat laser altimetry over small mountain... dh are signifi- 0.4 0.3 0.2 0.1 0 -10 -8 -6 -4 -2 0 2 dh ICESat-DEM [m] 4 6 8 10 Figure 4. Graph shows... [m] Surface elevation difference [m] D. Treichler and A. Kääb: ICESat laser altimetry over small mountain...–2146, 2016 2138 D. Treichler and A. Kääb: ICESat laser altimetry over small mountain... to zero-elevation difference between ICESat and reference DEM considering decreasing... application of saturation correction to ICESat elevations. Exclusion of saturated samples... ICESat trend. 5 5.1 Discussion Representativeness When combined with reference elevations from a DEM, ICESat.../10/2129/2016/ D. Treichler and A. Kääb: ICESat laser altimetry over small mountain.../10/2129/2016/ When relating ICESat trends to traditional glaciological measurements... D. Treichler and A. Kääb: ICESat laser altimetry over small mountain glaciers 8 7 6 dh ICESat-DEM.../mass changes as derived from ICESat, compared to traditional glaciological methods... density and ICESat track density (i.e. sample size), representativeness of the ICESat sample... areas may potentially yield valid ICESat glacier surface elevation change estimates.../10/2129/2016/ D. Treichler and A. Kääb: ICESat laser altimetry over small mountain... A. Kääb: ICESat laser altimetry over small mountain glaciers to co-register ICESat and.../10/2129/2016/ D. Treichler and A. Kääb: ICESat laser altimetry over small mountain..., the coarse spatial sample of ICESat represents southern Norwegian glaciers accurately... some campaigns. The applicability of ICESat in arbitrary glacierized regions depends... in reference DEM elevations exceed ICESat uncertainties by a magnitude. Elevation bias... the random effects from geographic ICESat footprint distribution. We developed a new... the reference DEMs rather than ICESat performance. ICESat provides an accurate sample...–2146, 2016 2144 D. Treichler and A. Kääb: ICESat laser altimetry over small mountain..., C. C. and Harding, D. J.: SRTM C-Band and ICESat Laser Altimetry Elevation Comparisons as..., M. A., Luthcke, S. B., and Blair, J. B.: Estimation of ICESat intercampaign elevation biases from comparison.../10/2129/2016/ D. Treichler and A. Kääb: ICESat laser altimetry over small mountain... Grosser Aletschgletscher, Swiss Alps, from ICESat Laser Altimetry Data and Digital..., 2010. Molijn, R. A., Lindenbergh, R. C., and Gunter, B. C.: ICESat laser full waveform analysis for...–2146, 2016 2146 D. Treichler and A. Kääb: ICESat laser altimetry over small mountain..., T., Minster, J., Spinhirne, J., and Thomas, R.: GLAS/ICESat L2 Global Land Surface Altimetry...



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0.19/5
... Brown Mark Carroll Vanessa Escobar ICESat-2 Applications Team NASA Goddard Space..., Cloud and land Elevation Satellite-2 (ICESat-2) Earth science satellite is the... prospects of ICESat-2 and are interested in how the ICESat-2 products will... to build a similar program for ICESat-2. The applications workshops are planned.... The ICESat-2 applications group will continue to work with the ICESat-2 SDT... and Heritage ........................................................................................................ 5 3. 2.1. ICESat Heritage Mission ................................................................................................................ 5 2.2. ICESat-2 Mission ............................................................................................................................ 6 Identifying the ICESat-2 Community ..................................................................................................... 6 3.1. Pre-Workshop... Items ............................................................................................................. 16 6. Appendices .......................................................................................................................................... 17 Appendix A: ICESat-2 Proposed Products Table ..................................................................................... 17 Appendix... Appendix D: Questions on ICESat-2 Applications Questionnaire ........................................................... 22 Appendix E: ICESat-2 Level 1 Science Requirements..., Cloud and land Elevation Satellite-2 (ICESat-2) Earth science satellite, scheduled for... the design of the first ICESat mission, ICESat-2 will use a micro-pulse... Background and Heritage 2.1. ICESat Heritage Mission The original ICESat mission was launched... to fill the gap between ICESat and ICESat-2 an airborne mission called... measurements in targeted areas. 5 2.2.ICESat-2 Mission The ICESat-2 mission is the third.... While ICESat-2 will build upon the heritage of the ICESat mission, the... ICESat-2 mission and the ATLAS instrument can be found on the ICESat-2 website http://icesat.gsfc.nasa.gov/icesat2... soon after launch. 3. Identifying the ICESat-2 Community 3.1. Pre-Workshop User Community... about the potential products from ICESat-2, respondents also reported a broad interest... 2). 7 Figure 2 Responses from Question 4 regarding ICESat-2 data products. Over 57% of... calculate the difference between successive ICESat-2 measurements at the same location... measurements from ICESat-2. The suite of proposed products for ICESat-2 is shown... from ICESat-2 and by comparing ICESat-2 measurements to heritage measurements from ICESat and airborne campaigns. The change measurements reported in ICESat-2 data... the differences in surface height. ICESat-2 will improve on existing information... the synergistic overlaps with other ICESat-2 potential products, (inland water and... the program is implemented into ICESat-2 applications (~3 years from launch). NIC... Luthcke from the ICESat-2 mission combined the use of ICESat and GRACE... all thematic groups of the ICESat-2 mission. 3.2.1.3. General conclusions of the... for joint product development (GRACE, ICESat) 3.2.2. Land Elevation and Vegetation The... products will use measurements from ICESat-2 along with ancillary information to... land/vegetation elevation products from ICESat-2 will significantly contribute to highly... products have been proposed for ICESat-2:      Ground Digital Terrain Model (DTM... planned for ICESat-2 to penetrate the canopy of forests. Although ICESat-2 data will have a much higher data density than ICESat data..., frequent products. In addition, the ICESat-2 data acquisition strategy will enable... they develop their algorithms for ICESat-2. 3.2.3. Oceans/Inland Water/Atmospheres The... as overall resource management perspective. ICESat-2 contributions in this area will... The atmospheric science component for ICESat-2 is capable of providing information... coordination between multiple missions including ICESat-2, SMAP, SWOT, Jason-3, and GRACE... for ICESat-2? And how can the activities leading up to the ICESat.... Applications from the heritage mission, ICESat, have been difficult to identify... being achieved. 16 6. Appendices Appendix A: ICESat-2 Proposed Products Table Product Number..., Cloud, and Land Elevation Satellite (ICESat-2) Applications Workshop April 12, 2012... applications to planned ICESat-2 products), create support for planned ICESat-2 data products... Welcome ICESat-2 Welcome, Charge to Workshop ICESat-2 Applications Requirements and strategy ICESat-2 Mission Overview MABEL Atlas simulator ICESat... areas that could benefit from ICESat-2 measurements  Provide quantitative information to... attendees. 21 Appendix D: Questions on ICESat-2 Applications Questionnaire 1. What type of... yes, which products? 24 Appendix E: ICESat-2 Level 1 Science Requirements 25 26



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.... 7, JULY 2008 1913 Comparison of ICESat Data With Airborne Laser Altimeter..., Cloud, and land Elevation Satellite (ICESat) are compared with high-resolution... several methods using lower resolution ICESat data. Under optimum conditions, i.e., when... larger than the ICESat footprint are present, the ICESat- and Airborne Topographic... within 2 cm. For other areas, ICESat tends to underestimate the freeboard..., Cloud, and land Elevation Satellite (ICESat), laser altimeter, remote sensing, sea..., Cloud, and land Elevation Satellite (ICESat) can monitor the third dimension... cover. A major challenge to convert ICESat-derived elevation to sea ice... evaluate the accuracy of the ICESat elevation data and the conversion... attempting to follow the predicted ICESat orbit. In addition to elevation... roughness can be derived from ICESat data. Surface roughness is important.... 2. Distances between predicted ICESat orbit, the actual ICESat ground spot measurements, and... ICESat ground spot measurement increased, the amount of overlap between the ICESat... 24 was coordinated with an ICESat overpass. The gray shades correspond...-E sea ice products. Considering that ICESat was switched on during the... when atmospheric conditions along the ICESat orbital track were expected to..., the time difference between the ICESat and aircraft measurements at the... predicted ICESat orbit. Fig. 2 shows the differences between the predicted ICESat orbit... was expectedly small, the actual ICESat ground spot measurements drifted away... expected to be small. A. ICESat Data ICESat measures the surface elevation relative..., and reflectivity can be measured. ICESat elevations are measured relative to... the same reference point. The ICESat elevation product is calculated by..., KURTZ et al.: COMPARISON OF ICESat DATA WITH AIRBORNE LASER ALTIMETER... effects. Reflectivity, as measured by ICESat, is also plotted. (b) Roughness comparison... the ICESat footprint, ATM elevation statistics within 55-m diameters of the ICESat... for 200-m diameters around the ICESat 1916 IEEE TRANSACTIONS ON GEOSCIENCE... possible between the ATM and ICESat measurements with increasing distance between... data, respectively. The reflectivity from ICESat is also plotted, for reference... the ICESat data product). The overall agreement between the ATM and ICESat... the outbound flight and the ICESat were indeed different. However, the.... 5. Comparison between the ATM and ICESat elevation data after the removal... data. (a) ICESat elevation compared with the 55-m ATM data. (b) ICESat elevation compared... are directly inferable from the ICESat waveform before comparing freeboard estimates..., but for consistency with the ICESat definition, we define the roughness... deviation in elevation within the ICESat footprint. A. Elevation and Roughness Table... than the actual ICESat footprint. The correlation between ICESat and ATM data... and the ICESat elevations suggests a small or negligible bias for ICESat of.... On an individual-footprint basis, ICESat and ATM roughness values are... data. (a) ICESat roughness compared with the 55-m ATM data. (b) ICESat roughness compared... the ATM coverage within the ICESat footprint. The correlation with only... representing the ICESat footprint (55-m-diameter circle around the ICESat footprint center... to cause a bias in the ICESat elevation. For moderately saturated returns... ICE MOTION CORRECTED ATM AND ICESAT ELEVATIONS AND ROUGHNESS FOR DIFFERENT.... The following summarizes the different ICESat-only methods used to determine... of the detector in the ICESat system causes the elevation measurements... coincident in time with 1) The ICESat transect is divided into separate... level for each region. 2) The ICESat transect is divided into separate... less variability between the different ICESat methods used, but each method... is within 1 cm of the ICESat-derived freeboards. Thus, the contamination... were correctly identified for both ICESat and the ATM. The contamination... thin-ice regions in the ICESat footprint can create significant biases... of the ICESat measurements for a flight north of Greenland. V. S UMMARY ICESat elevation... sea ice. Methods for converting ICESat elevation data into freeboard were... and for differentlength running means. ICESat sea ice elevations match very... measurements show that the current ICESat roughness product tracks changes in... level. The elevation measurements of ICESat provide a first step toward this... concentration, and freeboard in the ICESat footprint. Ice contamination was not... a more selective algorithm for finding ICESat tie points than what was.... [12] R. Kwok, H. J. Zwally, and D. Yi, “ICESat observations of Arctic sea ice...] R. Kwok, G. F. Cunningham, H. J. Zwally, and D. Yi, “ICESat over Arctic sea ice: Interpretation... Cloud and Land Elevation Satellite (ICESat) over Arctic sea ice: Retrieval...] C. F. Martin, R. H. Thomas, W. B. Krabill, and S. S. Manizade, “ICESat range and mounting bias estimation..., and J. P. DiMarzio, “Overview of the ICESat mission,” Geophys. Res. Lett., vol.... 1999. [27] H. J. Zwally et al., “ICESat’s laser measurements of polar ice...



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..., Cloud, and land Elevation Satellite (ICESat) Geoscience Laser Altimeter System (GLAS... the temporal coverage of each ICESat/GLAS product. Data are sampled.... Several kilometers typically separate the ICESat GLAS data tracks. Projection Two... below 64° N. The difference, D, between ICESat measured sea level and the... coverage of each ICESat/GLAS product. Temporal Resolution Each ICESat campaign period... Single-shot Error Budget for ICESat Elevation Measurements Error Source Precision... section of the NSIDC GLAS/ICESat L1 and L2 Global Altimetry... section of the NSIDC GLAS/ICESat L1 and L2 Global Altimetry... Sea Ice Thickness Data GLAS/ICESat L1 and L2 Global Altimetry... in Zwally et al. 2008. ICESat measures a surface elevation profile referenced..., Cloud, and land Elevation satellite (ICESat), from the SSM/I instrument on... Methods Freeboard is measured from ICESat elevation profiles (Zwally et al.... 1999). Thickness is estimated from ICESat freeboard and climatology snow depth... were derived from the corresponding ICESat point measurements of freeboard and... are estimated for each valid ICESat sea ice observation during the... are averaged together for each ICESat campaign. Those cells that do... and thickness are calculated from ICESat GLAS ground tracks using the... below 64° N. The difference, D, between ICESat measured sea level and the... oceans ΔH is applied to the ICESat elevation at the same time... ocean water waves. 5. Elevation. The ICESat measured surface elevation, H , the i_elev... the ie TOPEX/POSEIDON ellipsoid. ICESat surface elevations have instrument corrections... Description Elevation above the geoid ICESat measured surface elevation ΔHib Inverse... km running mean (h ) of elevation h. ICESat measures a surface elevation profile referenced... underestimating s freeboard. 9. h (D). The difference between ICESat measured sea level and the... 6) Where: Table 11. Difference Between ICESat Measured Sea Level and the... Description hd Difference between the ICESat measured sea level and the... directly used to do the ICESat shot to shot freeboard/thickness... pp. Kwok, R., and G. F. Cunningham. 2008. ICESat Over Arctic Sea Ice: Estimation..., H. J., D. Yi, R. Kwok, and Y. Zhao. 2008. ICESat Measurements of Sea Ice Freeboard..., H. J., B. Schutz, W. Abdalati, et al. 2002. ICESat's Laser Measurements of Polar Ice... GSFC Goddard Space Flight Center ICESat Ice, Cloud, and land Elevation...



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..., Cloud, and Land Elevation Satellite (ICESat) Lead Agency: National Aeronautics and..., Cloud, and Land Elevation Satellite (ICESat) which would retrieve global distributed.... For Further Information James Watzin ICESat Project Office NASA’s Goddard Space... Satellite (ICESat) mission. This EA discusses the objectives of the ICESat mission and its potential environmental impacts. ICESat is the... OF ENVIRONMENTAL ASSESSMENT............................................1-2 PROPOSED ACTION ..............................................................................2-1 2.1.1 ICESat Mission Development, Fabrication, Assembly, Test... Laser Altimeter System (GLAS)....................................2-2 2.1.3 ICESat Launch ............................................................................2-3 2.1.4 ICESat On-Orbit Mission Operations ..............................................2-4 2.1.5 Spacecraft... Vibration .................................................3-7 3.2.9 Cultural/Historical/Archaeological Resources...................................3-7 ICESAT ON-ORBIT MISSION OPERATION ................................................3-7 iv... Launch Site.....................................................................4-1 4.1.1.1 Environmental Impacts of ICESat Launch Preparation ........4-1 4.1.1.2 Environmental Impacts of... Processing Facility (PPF) ..............................4-9 4.1.1.3.3 Launch Failure ...........................................................4-9 4.1.2 ICESat On-Orbit Operation............................................................4-9 4.1.2.1 Normal Operation...).................................................. 2-4 2-3 ICESat orbiting above the Earth pictorial ....................................................... 2-5 LIST OF TABLES Table Page 2-1 ICESat... Vehicle (First Stage and GEMs) ................................................................................................ 4-2 4-2 ICESat hazardous chemicals/materials .......................................................... 4-6 4-3 REs and..., Cloud, and Land Elevation Satellite (ICESat) mission would provide data that... global climate change. Specifically, the ICESat mission would measure changes of... 1999). Additional objectives of the ICESat mission include (1) measurement of cloud... ALTERNATIVES PROPOSED ACTION The proposed ICESat mission is a cooperative effort between..., University of Texas, Austin, Texas. 2.1.1 ICESat Mission Development, Fabrication, Assembly, Test... at BATC. ICESat spacecraft features are shown below: 2-1 Table 2-1. ICESat Spacecraft Features... a bell curve. 2.1.3 ICESat Launch NASA GSFC proposes to launch ICESat in late... space launch vehicle 2.1.4 ICESat On-Orbit Mission Operations ICESat would be launched... discussed below. 2-4 Figure 2-3. Diagram of ICESat orbiting above the Earth The... the data archive facilities. The ICESat Science Computing Facility (SCF), which... for ICESat science data. 2.1.5 Spacecraft Decommissioning at the End-of-Mission ICESat... to five years, total. Therefore, ICESat would have sufficient spacecraft expendables... the Earth’s radiation budget. Although ICESat is designed to collect information... medium size satellites such as ICESat. Alternative launch vehicles include the... the launch site, because the ICESat mission science requires a high inclination... modifications are proposed for the ICESat mission. 3.3 ICESAT ON-ORBIT MISSION OPERATION... sonic boom. 4.1.1.1 Environmental Impacts of ICESat Launch Preparation Hazardous materials are... endangered species. 4.1.1.2.10 Socioeconomics The ICESat launch from VAFB would be... wastes. 4.1.1.2.13 Environmental Justice The ICESat launch would be a routine launch... the U.S. Census Bureau criteria. The ICESat launch would not have disproportionate... launch sites. 4-5 4.1.1.2.14 Hazards The ICESat presents routine hazards, which are... would augment visual inspection. Table 4-2. ICESat hazardous chemicals/materials Substance Quantity... environmental hazards connected to the ICESat mission exist, a number of safety... objectives for pollution prevention. The ICESat mission, during spacecraft processing, would... reducers have been eliminated from ICESat processing. The cleaning at instrument... would be anticipated. 4.1.2 ICESat On-Orbit Operation The ICESat on-orbit laser..., separation and deployment nor does ICESat release any operational debris during.... Effect of ICESat Off-Nadir pointing maneuver The ICESat spacecraft would occasionally... area for ICESat is 3.63 m2 (39 ft2). Therefore, ICESat satisfies the... environment. 4-12 4.1.2.3 Accident Scenario The ICESat laser would not be activated... exposed to the laser energy. ICESat utilizes a hydrazine monopropellant pressurized with..., Cloud, and Land Elevation Satellite (ICESat) Mission Specification, MDC 99H0061. Klock..., Cloud and Land Elevation Satellite (ICESat) Project Plan, 401-PG7120.2.3. NASA... Center Hampton, Virginia. NASA 2000b. ICESat GLAS Laser Safety Analysis Report..., Cloud and Land Elevation Satellite (ICESat) Orbital Debris Assessment Report, January...



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...ökull, Iceland from Cloud-Cleared ICESat Repeat Profiles and GPS Ground..., Cloud, and land Elevation Satellite (ICESat) ‘repeat tracks,’ fifteen times from... temporallyclosest ICESat profiles and the GPS-derived digital-elevation model (DEM) (ICESat... deviations of 3 to 4 m. Differencing all ICESat repeats from the DEM shows... that the elevation changes where ICESat tracks 0046 and 0307 cross... during the time frame when ICESat data indicates substantial losses. This... the locations of the two ICESat reference tracks across the ice..., Cloud, and land Elevation Satellite (ICESat) laser altimetry profiles (Figure 2 and... each repeat of the two ICESat profiles that passed the initial... northeast facing slopes. 117 ICESat Data ICESat Track Data Release Profile Date... the 3-digit tracks used during ICESat 8-day patterns in 2003; Column... 6 and 7 contain the local mean ICESat laser transmit and received energy... Figure 3a. Comparison of fifteen ICESat Track 0046 geoid-corrected elevation... the ICESat elevations and the right axis is for the ICESat-DEM elevation differences. A ‘high-cloud’ ICESat elevation (3B... Figure 3b. Comparison of fifteen ICESat Track 0307 geoid-corrected elevation... the ICESat elevations and the right axis is for the ICESat-DEM elevation differences. Multiple ‘high-cloud’ ICESat elevations (3C... of Drangajökull using two ICESat altimetry ‘repeat tracks’ that were... a quantitative assessment of the available ICESat altimetry data. The DEM was... issues as discussed later. 120 ICESat repeat-elevation profiles over the... 8-day repeat tracks (i.e., in ~8 days, ICESat would being the pattern again... shots per second) along all ICESat ground tracks. Depending on cloud... during ICESat various operational periods (see http://nsidc.org/data/icesat/laser_op_periods... Altimeter System (GLAS) that is ICESat's primary sensor has decreased with... at http://nsidc.org/data/icesat/yxx_release_numbers.html) explored here but...-change assessments. This study evaluates ICESat repeat profile accuracy relative to...’s ability to enable comparisons of ICESat repeat tracks that are spread... section, the remaining ‘cloud-cleared’ ICESat data are used to derive... should represent a validation of the ICESat mission.] METHODOLOGY To assess elevation... as cirrus, can impact multiple ICESat repeats (see Table 1). To account... of the topography sampled by ICESat’s discrete footprints and flatter topography... should be small relative to ICESat-DEM differences derived from the... values adjacent to each ‘good’ ICESat elevation value’s location were interpolated... study are from GLA06 (GLAS/ICESat L1B Global Elevation Data, see....org/data/ gla06.html). The ICESat elevations are referenced to the... of the time series of ICESat-DEM elevation differences from late... indicate northern hemisphere seasons and ICESat operations periods are indicated (grey... elevation’ data to compare). Substantial ICESat elevation data were acquired from... ice-cap surface elevations from ICESat repeat track data and, consequently... Drangajökull’s elevation trends. First, ICESat tracks and/or crossovers (an... that enables consistency checks on ICESat's overall performance) may not be... ICESat overpass (Figure 3). Third, examination of the elevation differences between the ICESat... Figure 3, elevation differences). And fourth, ICESat’s ‘repeat tracks’ (2 to 3 times a year... were then interpolated to match ICESat’s laser footprint locations. DEM slopes... data types. For example, if ICESat locations relative to the DEM... (see Figure 3). To test this, ICESat elevations were converted to a WGS... using the available, more complete, ICESat 0047 and 0307 passes. Even.... Currently, only unpublished assessments of ICESat’s positioning knowledge and accuracy are... so may not represent a particular ICESat track in an operations period... see http://nsidc.org/data/icesat/laser_op_periods.html - table of attributes... 1 m with 3 to 4 m standard deviations (the ICESat elevations are above the DEM..., because the topography along the ICESat profiles was usually irregularly sampled... DEM topography allows the available ICESat – DEM elevation differences to be... reduction in elevation returns from ICESat as laser transmit energy dropped... of the ICESat-DEM differences as would additional clear ICESat passes. CONCLUSIONS Our analysis shows that ICESat repeat altimetry... in comparing the ICESat elevations to the DEM, these ICESat-DEM differences... and especially elevation changes from ICESat data alone through cloudy skies... profiles throughout the years of ICESat's operations makes it very difficult... to integrate the latest available ICESat data relative to well-constrained... uncertainties in ICESat laser pointing and ranging knowledge. In addition, ICESat repeat... thus decrease elevation change uncertainty. ICESat is clearly observing the underlying..., JP. 2005. Overview of the ICESat mission: Geophysical Research Letters 32..., RJ. and Suchdeo, VP. 2006, ICESat Antarctic ice sheet elevations. Preliminary...



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... Cap as Measured by the ICESat and EnviSAT Satellite Altimeters 4.1 Abstract... Radar Altimeter 2 . . . . 2.5 Laser Altimeter Systems . . . . . . . . . . 2.5.1 ICESat Geoscience Laser Altimeter 2.6 Brief History... Ice Greenland 5.1 Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3 Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3.1 ICESat GLAS . . . . . . . . . . . . . . . . . . . . . . . 5.3.2 EnviSAT RA-2 . . . . . . . . . . . . . . . . . . . . . . . 5.3.3 RACMO2 climate... extension . . . . . . 7.4.2 CryoSat-2 SIRAL-2 . . . . . . . . . . . . . . . . . . . . 7.4.3 Sentinel-3 SRAL . . . . . . . . . . . . . . . . . . . . . . 7.4.4 ICESat-2 ATLAS . . . . . . . . . . . . . . . . . . . . . . 7.5 Wider Implications and the...-2 and GLAS A.2.2 RA-2 specific functions . . . . . . . . . . A.2.3 ICESat GLAS specific functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 121... System GrIS Greenland Ice Sheet ICESat Ice, Cloud and land Elevation..., Cloud and land Elevation Satellite (ICESat) add to the knowledge of... ice sheet elevation change using ICESat measurements during 2003-2008. Both... is the case with the ICESat GLAS (see Section 2.5.1) retracker: a gaussian... adjustable solar panel arrays, like ICESat (see subsection 2.5.1), will oscillate due... array motions. In case of ICESat, these oscillations produced tens of... pointing uncertainty of GLAS onboard ICESat (which utilized both star trackers... the Earth’s surface. Again using ICESat as an example, an uncertainty... saturation is a known problem with ICESat GLAS (see subsection 2.5.1) waveforms. For... thesis, albeit on a different planet. 2.5.1 ICESat Geoscience Laser Altimeter System The... on board NASA’s ICESat. The main objective of ICESat was to measure... Greenland and Antarctic ice sheets. ICESat also monitored cloud height and... elevation (Zwally et al., 2002). ICESat was launched in January 2003... spring 2003 to fall 2009, ICESat completed 17 such operation periods...-Poseidon ERS-2 GFO Jason-1 EnviSAT ICESat Cryosat Jason-2 Cryosat-2 Agency NASA... was tackled by differencing the ICESat alongtrack measured elevations and the... Cap as Measured by the ICESat and EnviSAT Satellite Altimeters” Authors... elevation measurements acquired by the ICESat GLAS and EnviSAT RA-2 satellite... from two satellite altimeter missions (ICESat GLAS and EnviSAT RA-2) to... Geoscience Laser Altimeter System The ICESat Geoscience Laser Altimeter System (GLAS... board NASA’s ICESat satellite. The main objective of the ICESat mission is... Greenland and Antarctic ice sheets. ICESat also monitors cloud height and... publicly available ICESat data were from spring 2008. The ICESat data used in this paper are the GLAS/ICESat L1B... in ice dynamics. 1.5 1 Relative elevation [m] 0.5 0 −0.5 −1 −1.5 ICESat GLAS −2 EnviSAT RA−2 −2.5 2002 2003... Altimeter System (GLAS) onboard NASA’s ICESat to map the elevation change..., Cloud and land Elevation satellite (ICESat) (Zwally et al., 2002), and... crossover point on the FIIC. 5.3.1 ICESat GLAS GLAS provided near global... requirement. The ground tracks of ICESat from different years may have...) to obtain elevation trends between ICESat tracks where no measurements were... and a better temporal resolution than ICESat GLAS. Even if short time... studies. 7.4.4 ICESat-2 ATLAS The Ice, Cloud, and land Elevation Satellite-2 (ICESat-2), scheduled... of the ICESat mission. The main payload of the ICESat-2 will be... the 170 m spacing of GLAS. ICESat-2, if successful, will provide data... half of a decade 101 Figure 7.2: ICESat-2 measurement configuration (Source: NASA) from..., C., Quinn, K., & Bills, B. 2005. Assessment of ICESat performance at the Salar de... combined ICESat and ASTER observations. GEOPHYSICAL RESEARCH LETTERS, 35(17). ICESat-2 WWW page. 2011 (May). ICESat-2 Mission Home Page (http://icesat.gsfc... Review Board Executive Summary, http://icesat.gsfc.nasa.gov/docs/IGARB... of Svalbard glaciers derived from ICESat laser altimetry. REMOTE SENSING OF... of ICESat/GLAS Data Releases (http://nsidc.org/data/icesat/data releases..., JP. 2005. Overview of the ICESat Mission. GEOPHYSICAL RESEARCH LETTERS, 32...., Suchdeo, VP., & Fricker, HA. 2006. ICESat Antarctic elevation data: Preliminary precision... of Greenland’s ice sheet from ICESat data using overlapping footprints. REMOTE... of the Ross Embayment from ICESat crossovers. GEOPHYSICAL RESEARCH LETTERS, 32... Bridge the Observational Gap Between ICESat And ICESat-2. IEEE International Symposium on.... Space Laser Transmitter Development for ICESat-2 Mission. In: Clarkson, WA and..., B., Quinn, K., Palm, S., Spinhirne, J., & Thomas, R. 2002. ICESat’s laser measurements of polar ice..., & R., Thomas. 2003, updated 2009. GLAS/ICESat L1B Global Elevation Data V018... difference from each time series. A.2.3 ICESat GLAS specific functions Data used..., Cloud, and land Elevation Satellites (ICESat) Geoscience Laser Altimeter System (GLAS...