Climate Science News

10-16 July 2017 week

AVISO Climate Change News - Thu, 2017-07-20 01:00
Antarctic Ice Shelf Sheds Massive Iceberg (Earthobservatory, 2017/07/12)
Antarctique : l’un des plus gros icebergs de l’histoire vient de se détacher ! (SciencePost, 2017/07/12)
Warm winter events in Arctic becoming more frequent, lasting longer (Science Daily, 2017/07/11)
Dans l’Océan, les coraux produisent leur propre lumière pour survivre (SciencePost, 2017/07/11)
On line availability of articles depends on the Newspaper/magazine. We can't thus certify that above articles will be freely and permanently available.

Categories: Climate Science News

A recent slowdown

NSIDC Artic Sea Ice News - Tue, 2017-07-18 10:14

Arctic extent nearly matched 2012 values through the first week of July, but the rate of decline slowed during the second week. Weather patterns were unremarkable during the first half of July.

Overview of conditions

Figure 1. Arctic sea ice extent for July 17, 2017 was 7.88 million square kilometers (3.04 million square miles). The orange line shows the 1981 to 2010 average extent for that day. Sea Ice Index data. About the data

Credit: National Snow and Ice Data Center
High-resolution image

As of July 17, Arctic sea ice extent stood at 7.88 million square kilometers (3.04 million square miles). This is 1.69 million square kilometers (653,000 square miles) below the 1981 to 2010 average, and 714,000 square kilometers (276,000 million square miles) below the interdecile range. Extent was lower than average over most of the Arctic, except for the East Greenland Sea (Figure 1). Hudson Bay was nearly ice free by mid July, much earlier than is typical, but in line with what has been observed in recent years.

Conditions in context

Figure 2a. The graph above shows Arctic sea ice extent as of July 17, 2017, along with daily ice extent data for five previous years. 2017 is shown in blue, 2016 in green, 2015 in orange, 2014 in brown, 2013 in purple, and 2012 as a dotted brown line. The 1981 to 2010 median is in dark gray. The gray areas around the median line show the interquartile and interdecile ranges of the data. Sea Ice Index data.

Credit: National Snow and Ice Data Center
High-resolution image

Figure 2b. This map compares sea ice extent for July 11 in 2017 and in 2012. White shows where ice occurred only in 2012, medium blue is where ice occurred only in 2017, and light blue is where ice occurred in both years.

Credit: National Snow and Ice Data Center
High-resolution image

Through the first week of July, extent closely tracked 2012 levels. The rate of decline then slowed, so that as of July 17, extent was 169,000 square kilometers (65,300 square miles) above 2012 for the same date (Figure 2a). The spatial pattern of ice extent differs from 2012, with less ice in the Chukchi and East Siberian Seas in 2017, but more in the Beaufort, Kara, and Barents Seas and in Baffin Bay (Figure 2b).

Visible imagery provides up close details  RESEARCHER'S NAME/ORGANIZATION *or * National Snow and Ice Data Center| High-resolution image

Figure 3a. This image from the NASA Moderate Resolution Imaging Spectroradiometer (MODIS) shows sea ice in the Canadian Archipelago on July 3, 2017. The blue hues indicate areas of widespread melt ponds on the surface of the ice.

Credit: Land Atmosphere Near-Real Time Capability for EOS (LANCE) System, NASA/GSFC
High-resolution image

sea ice floes

Figure 3b. The Sentinel-2 satellite captured this image of large sea ice floes in Nares Strait on July 8, 2017.

Credit: European Space Agency
High-resolution image

MODIS image of arctic

Figure 3c. This false-color composite image of the Arctic is based on NASA MODIS imagery from July 4 to 10. Most clouds are eliminated by using several images over a week, but some clouds remain, particularly over the ocean areas.

Credit: NASA/Canadian Ice Service
High-resolution image

NSIDC primarily relies on passive microwave data because it provides complete coverage—night and day, and through clouds—and because it is consistent over its long data record. However, other types of satellite data, for example visible imagery from the NASA MODIS instrument on the Aqua and Terra satellites or from the European Space Agency Sentinel 2 satellite, can sometimes provide more detail. When skies clear, details of the ice cover can be seen, including leads, individual ice floes and melt ponds. For example, on July 3 in the Canadian Archipelago, 1-kilometer resolution MODIS imagery shows that the ice surface has a distinctive blueish hue due to the presence of melt ponds on the surface (Figure 3a). Higher resolution Sentinel-2 imagery (10 meters, Figure 3b) on the other hand provides up close detail on individual melt ponds on the ice floes.

The Arctic is a cloudy place, and generally, it is difficult to obtain a clear-sky image of the entire region. However, if images are compiled, or composited, over several days, most of the region may have at least some clear sky. This approach can yield a composite image that is mostly cloud-free. The Canadian Ice Service uses this approach to create a weekly nearly cloud-free composite image of the Arctic (Figure 3c). However, because the ice cover moves (typically several kilometers per day) and melts (during the summer), over the week-long composite period, fine details that can be seen in the daily imagery are not as evident because they have been “smeared” out over the week.

An ice-diminished Arctic

In response to diminishing ice extent, the US Navy has been holding a semi-annual symposium to bring together scientists, policy makers, and others to discuss the sea ice changes and their impacts. The seventh Symposium is taking place this week in Washington, DC, and will be attended by NSIDC scientists Mark Serreze, Walt Meier, Florence Fetterer, and Ted Scambos.

Tendency for warmer winters is increasing

A new study published this week in Geophysical Research Letters by Robert Graham at the Norwegian Polar Institute shows that warm winters in the Arctic are becoming more frequent and lasting for longer periods of time than they used to. Warm events were defined by when the air temperatures rose above -10 degrees Celsius (14 degrees  Fahrenheit). While this is still well below the freezing point, it is 20 degrees Celsius (36 degrees Fahrenheit) higher than average. The last two winters have seen temperatures near the North Pole rising to 0 degrees Celsius. While an earlier study showed that winter 2015/2016 was the warmest recorded at that time, the winter of 2016/2017 was even warmer.

Reference

Graham, R. M., L. Cohen, A. A. Petty, L. N. Boisvert, A. Rinke, S. R. Hudson, M. Nicolaus, and M. A. Granskog. 2017. Increasing frequency and duration of Arctic winter warming events, Geophys. Res. Lett., 44, doi:10.1002/2017GL073395.

Categories: Climate Science News

3-9 July, 2017 week

AVISO Climate Change News - Wed, 2017-07-12 23:51
Réchauffement climatique: et cet iceberg géant qui finit de se détacher en Antarctique... (Sud Ouest, 2017/07/08)
Pour étudier les effets du changement climatique dans les océans : le navire Dr Fridtjof Nansen explore les eaux sénégalaises (Le Quotidien, 2017/07/07)
Le réchauffement climatique pourra entraîner des pluies diluviennes sur le Sahel (Sciences Avenir, 2017/07/06)
Veteran Ocean Satellite to Assume Added Role (Spacedaily, 2017/07/03)
On line availability of articles depends on the Newspaper/magazine. We can't thus certify that above articles will be freely and permanently available.

Categories: Climate Science News

Temporary unavailability of the LAS Service on July 10, 2017

AVISO Climate Change News - Mon, 2017-07-10 23:31
For maintenance reason, the LAS Service (http://las.aviso.altimetry.fr/) has been unavailable from...
Categories: Climate Science News

Temporary unavailability of the Bulletin Service on July 06, 2017

AVISO Climate Change News - Thu, 2017-07-06 05:15
For maintenance reason, the Bulletin Service (http://bulletin.aviso.altimetry.fr/) is unavailable...
Categories: Climate Science News

Water JPI 2017 Joint Call opening soon!

AVISO Climate Change News - Thu, 2017-07-06 00:27
The Water JPI will launch on 30 August 2017 its new Joint Call on the topic “Water resource management in support of the United Nations Sustainable Development Goals”. For more information, please visit the 2017 Joint Call webpage here!
Categories: Climate Science News

25 Years of Progress in Radar Altimetry Symposium - 24-29 September 2018, Azores

AVISO Climate Change News - Thu, 2017-07-06 00:14

Following on from the "15 Years of Progress in Radar Altimetry"  Symposium in 2006 and the "20 Years of Progress in Radar Altimetry"  Symposium in 2012, in Venice-Lido, Italy, both deemed very successful landmarks by the participants and the readership of the Proceedings, we are now at the twenty-five year anniversary of the launch of ERS-1 and TOPEX/POSEIDON. To mark this occasion the  European Space Agency, in collaboration with the French Space Agency,  CNES, is organising an exceptional Symposium on "25 Years of Progress in Radar Altimetry". This event will also be sponsored by other partner agencies and organisations supporting the development of altimetry. Along with this symposium, several related events will take place on the same week, including the annual meeting of the Ocean Surface Topography Science Team (OSTST) and the International Doris Service (IDS) workshop, as well as other thematic workshops still to be organised; potential topics are Sea Level for Climate, Coastal Zone, Space for Hydrology, Argo, etc. These events will be held over 6 days, from 24 to 29 of September 2018, in Ponta Delgada, São Miguel Island, Azores Archipelago (Portugal). 

Please consider your participation at this exceptional event and reserve the week from 24 to 29 September 2018 in your agenda. For the symposium, a call for papers with detailed information and deadlines will be sent subsequently, along with the details of a dedicated web site to submit your contributions to be reviewed by the Scientific Committee. For OSTST and IDS meetings, additional information and call for contributions will be sent out and linked to the same website.
    

Looking forward to another great "slow-time" event like the 15 and 20 Years of Progress in Radar Altimetry held in Venice in 2006 and 2012, an exceptional scientific Symposium on "25  Years  of  Progress  in  Radar  Altimetry"!

Looking forward to your participation!


Jérôme Benveniste and Pascal Bonnefond
on behalf of the 25 Years of Progress in Radar Altimetry Symposium Organising Committee

Pro Memoria:

The web site for 15YPRA is accessible at http://earth.esa.int/venice06
The web site for 20YPRA is accessible at http://esaconferencebureau.com/2012-events/12c01

Proceedings of 15YPRA on CD-Rom and athttp://www.esa.int/esapub/conference/toc/tocSP614.pdf
Proceedings of 20YPRA on CD-Rom and at http://www.spacebooks-online.com/product_info.php?cPath=104&products_id=17546


SUMMARY AND RECOMMENDATIONS FROM THE “20 YEARS OF PROGRESS IN RADAR ALTIMETRY” SYMPOSIUM, by Jérôme Benveniste, Rosemary Morrow, Jean-Louis Fellous and Albert Fischer is available at  http://esamultimedia.esa.int/multimedia/publications/SP-710/session_summaries.pdf

Categories: Climate Science News

25 June - 2 July, 2017 week

AVISO Climate Change News - Wed, 2017-07-05 23:44
Changement climatique, les atolls résistent bien à l'élévation du niveau de la mer (Tahiti infos, 2017/06/30)
Record June Temperatures in Western Europe (WWA, 2017/06/29)
Comment le phytoplancton domine les océans ? Des chercheurs grenoblois ont la réponse (Placegrenet, 2017/06/27)
C’est donc prouvé, le niveau de la mer monte plus vite à cause de la fonte des glaces (Mashable, 2017/06/27)
Le Groenland, responsable de la hausse du niveau des océans (Le Figaro, 2017/06/26)
Climat. À lui seul, le Groenland peut faire monter les océans de 7 mètres (Ouest France, 2017/06/26)
Climat: les océans se réchauffent plus rapidement que prévu (BFM TV, 2017/06/27)
On line availability of articles depends on the Newspaper/magazine. We can't thus certify that above articles will be freely and permanently available.

Categories: Climate Science News

Arctic ice extent near levels recorded in 2012

NSIDC Artic Sea Ice News - Wed, 2017-07-05 13:00

Contrasting with the fairly slow start to the melt season in May, June saw the ice retreat at a faster than average rate. On July 2, Arctic sea ice extent was at the same level recorded in 2012 and 2016. In 2012, September sea ice extent reached the lowest in the satellite record. As a new feature to Arctic Sea Ice News and Analysis, NSIDC now provides a daily updated map of ice concentration in addition to the daily map of ice extent.

Overview of conditions Figure 1. Arctic sea ice extent for June 2017 averaged 11.06 million square kilometers (4.27 million square miles).

Figure 1. Arctic sea ice extent for June 2017 averaged 11.06 million square kilometers (4.27 million square miles). The magenta line shows the 1981 to 2010 average extent for that month. Sea Ice Index data. About the data

Credit: National Snow and Ice Data Center
High-resolution image

Arctic sea ice extent for June 2017 averaged 11.06 million square kilometers (4.27 million square miles), the sixth lowest in the 1979 to 2017 satellite record. The average June 2017 extent was 900,000 square kilometers (348,000 square miles) below the 1981 to 2010 long-term average, and 460,000 square kilometers (178,000 square miles) above the previous record low set in 2016.

Continuing the pattern seen in May, sea ice extent at the end of the month remained below average in the Chukchi Sea and in the Barents Sea. Ice extent was at average levels in the Greenland Sea. Areas of low concentration ice have developed along the ice edge and coastal seas.

Based on imagery from the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the NASA Terra and Aqua satellites, summer melt ponds atop the ice cover were somewhat slow to develop. However, there is now widespread melt pond coverage in the Canadian Archipelago and the Laptev and East Siberian Seas. Data from the Advanced Microwave Scanning Radiometer 2 (AMSR-2) instrument analyzed by the University of Bremen, as well as MODIS imagery, indicate that melt ponds have also developed over the Central Arctic Ocean. Researchers in Dease Strait in Northern Canada have observed melt ponds forming about two weeks earlier than average. Melt ponds are important as they decrease the albedo or reflectivity of the ice surface, which hastens further melt.

Conditions in context Figure 2. The graph above shows Arctic sea ice extent as of July 4, 2017, along with daily ice extent data for five previous years. 2017 is shown in blue, 2016 in green, 2015 in orange, 2014 in brown, 2013 in purple, and 2012 in dashed red. The 1981 to 2010 median is in dark gray. The gray areas around the median line show the interquartile and interdecile ranges of the data.

Figure 2. The graph above shows Arctic sea ice extent as of July 4, 2017, along with daily ice extent data for five previous years. 2017 is shown in blue, 2016 in green, 2015 in orange, 2014 in brown, 2013 in purple, and 2012 in dashed red. The 1981 to 2010 median is in dark gray. The gray areas around the median line show the interquartile and interdecile ranges of the data. Sea Ice Index data.

Credit: National Snow and Ice Data Center
High-resolution image

The rate of decline in ice extent was fairly steady through the month, and the average rate of decline of 81,800 square kilometers (31,600 square miles) per day was slightly faster than the 1981 to 2010 long-term average of 56,300 square kilometers (21,700 square miles) per day. On July 2, extent was the same as that recorded in 2012 and 2016. The year 2012 ended up with the lowest September extent in the satellite record.

June air temperatures were modestly above average (1 to 3 degrees Celsius or 2 to 5 degrees Fahrenheit) in a band spanning the Arctic Ocean roughly centered along the date line and the prime meridian. This contrasts with below-average temperatures over the eastern Beaufort Sea and Canadian Arctic Archipelago and the Barents and Laptev Seas (1 to 3 degrees Celsius, 2 to 5 degrees Fahrenheit). Atmospheric pressures at sea level were below-average over the Kara Sea and extending north of the Laptev Sea.

June 2017 compared to previous years Figure 3. Monthly June ice extent for 1979 to 2017 shows a decline of 3.7 percent per decade.

Figure 3. Monthly June ice extent for 1979 to 2017 shows a decline of 3.7 percent per decade.

Credit: National Snow and Ice Data Center
High-resolution image

The linear rate of decline for June is 44,300 square kilometers (17,100 square miles) per year, or 3.7 percent per decade.

Ice thickness  University of Washington Pan-Arctic Ice Ocean Modeling and Assimilation System

Figure 4. This figure shows that sea ice thicknesses for May 2017 were below the 2000 to 2015 average over most of the Arctic Ocean (areas in blue) except for the region north and west of the Svalbard archipelago (areas in red).

Credit: University of Washington Pan-Arctic Ice Ocean Modeling and Assimilation System
High-resolution image

The University of Washington Seattle Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) regularly produces maps of ice thickness anomalies (departures from the long-term average). PIOMAS is based on a coupled ice-ocean model that is driven by data from an atmospheric reanalysis, and also assimilates data on observed ocean conditions and ice thickness (e.g., from NASA IceBridge). The PIOMAS analysis suggests that, relative to the average over the period 2000 to 2015, ice thickness for May 2017 (when the melt season was just beginning) was below average over most of the Arctic Ocean, especially in the Chukchi Sea and north of the Canadian Arctic Archipelago. A small region with above-average ice thickness is depicted over the Atlantic side of the Arctic north and west of the Svalbard Archipelago, and in the Greenland Sea. Starting the melt season with below-average ice thickness raises the likelihood of having especially low September ice extent.

Freezing degree days and ice thickness Figure 5. The figure shows departures from average in cumulate freezing degree days, extending from July 1 for a given year through July 1 of the next year, along with the range, 15th through 85th percentile and 30th to 70th percentile values over the base period 1981 through 2010.

Figure 5. The figure shows departures from average in cumulate freezing degree days, extending from July 1 for a given year through July 1 of the next year, along with the range, 15th through 85th percentile and 30th to 70th percentile values over the base period 1981 through 2010.

Credit: National Snow and Ice Data Center
High-resolution image

Cumulative Freezing Degree Days (FDD) is a simple measure of how cold it has been and for how long. Cumulative FDD is the sum of daily mean temperatures below zero from some start date. Here we start on July 1. Cumulative FDD is related to ice thickness because, on average, years with longer periods of temperatures below freezing will have more ice growth. A simple empirical model that has been used by scientists relates ice thickness to the square root of cumulative FDD.

Anomalies (departures from the average) in cumulative FDD illustrate the coldness of a given period relative to the long-term average (1981 to 2010). Figure 5 shows that most of the period from July 2016 to July 2017 was extremely mild and was milder (less cold) than both 2006 to 2007 and 2011 to 2012. September of both 2007 and 2012 ended up with very low September sea ice extent. This is consistent with below-average ice thickness seen in the PIOMAS data. Although conditions cooled in May and June, this likely had little impact on ice thickness. This is because ice in the Arctic reaches its maximum thickness earlier in the season during March or April. As noted earlier, ice retreated at a fast rate throughout June. This is likely linked to a thinner than average ice cover as seen in the PIOMAS analysis.

Sudden Antarctic sea ice decline in late 2016

A slight decrease in the rate of sea ice growth at the end of June brought Antarctic sea ice extent back to daily record lows. Sea ice extent in the Bellingshausen, eastern Amundsen, and western Ross Seas was below average.

Our post on December 2016 ice conditions highlighted a precipitous drop in Antarctic sea ice extent in the Weddell and Ross Sea sectors during September, October, and November of 2016. A recent study by John Turner and colleagues links this pattern of sea ice decline to a series of strong storms, marked by long periods of warm winds from the north. These changing weather conditions are associated with large shifts in the Southern Annual Mode index (SAM index).

Further reading

Turner, J., T. Phillips, G. J. Marshall, J. S. Hosking, J. O. Pope, T. J. Bracegirdle, and P. Deb. 2017. Unprecedented springtime retreat of Antarctic sea ice in 2016, Geophysical Research Letters, 44, doi:10.1002/2017GL073656.

Categories: Climate Science News

New product: Mesoscale Eddy Trajectory Atlas

AVISO Climate Change News - Mon, 2017-07-03 05:00
We are proud to announce the release of a new AVISO+ dataset, the "Mesoscale Eddy Trajectory Atlas"...
Categories: Climate Science News

June 2017: Eddies everywhere

AVISO Climate Change News - Mon, 2017-07-03 00:24
Eddies are ubiquitous in the ocean. They can be tracked and followed day by day for nearly 25 years.
Categories: Climate Science News

19-25 June 2017 week

AVISO Climate Change News - Thu, 2017-06-29 06:48
Satellite image showcases centuries of desertification in India (Space Daily, 2017/06/21)
How phytoplankton rule the oceans (Phys.Org, 2017/06/21)
L’agence spatiale française s’attaque au réchauffement climatique (Le Monde, 2017/06/21)
Réchauffement climatique : les coraux de la mer Rouge font de la résistance (Le Quotidien, 2017/06/21)
On line availability of articles depends on the Newspaper/magazine. We can't thus certify that above articles will be freely and permanently available.

Categories: Climate Science News

Temporary unavailability of the CNES ftp server on June 29, 2017

AVISO Climate Change News - Tue, 2017-06-27 04:53
For maintenance reason, the Cnes ftp server (ftp://avisoftp.cnes.fr) will be unavailable on June...
Categories: Climate Science News

[L2P Sentinel-3A] Operational release of Sentinel-3A Value Added products

AVISO Climate Change News - Thu, 2017-06-22 06:30
All information on the front-page news.
Categories: Climate Science News

[Sentinel-3A] Operational release of Sentinel-3A Value Added products

AVISO Climate Change News - Thu, 2017-06-22 05:30
The products processed by the Sentinel-3 Level 2P/L3 Marine Altimetry Service (CNES/CLS consortium under an EUMETSAT Contract, funded by the European Union) have been delivered as a pre-operational service on the AVISO+ dissemination since December 15th, 2016 for L2P NRT, January 17th, 2017 for L2P STC (see AVISO+ web page product) and on the CMEMS Catalogue since April 19th, 2017 for L3 NRT/STC products. The Products These products are derived from the SRAL (dual-frequency Synthetic Aperture Radar Altimeter) instrument onboard Sentinel-3. The L2P products are mono-mission global products containing 1 Hz along-track corrected sea surface heights with respect to a mean sea surface, corrections and geophysical parameters. The last versions of altimetric standards are used and there is a homogenised format for all satellites. They are generated in Near-Real Time (NRT), Short-Time Critical (STC) and Non-Time-Critical (NTC) timeliness. They are distributed in the user friendly NetCDF format. The added value compared to level 2 products is:
  • The update of geophysical standards to calculate sea level anomalies, such as
    • FES2014 ocean tide
    • CNES/CLS 2015 mean sea surface referenced to a 20 year reference period
    • Filtered ionospheric correction
    • Dynamical atmospheric correction for L2P NRT products (instead of only inverted barometer height correction in the case of L2 NRT products).
  • A validity flag to remove spurious measurements
  • The distribution of L2P SLA near real time products splitted in passes (instead of 10 minute granules for L2 near real time products).
The L3 Sentinel-3A products are global along-track products that contain time, sea level anomaly and absolute dynamic topography only for valid marine surfaces. The L3 products have under-gone a multi-mission cross-calibration process versus a reference mission (Jason-3).  The dissemination Considering the success of the pre-operational service delivery, EUMETSAT decided to begin the operational phase. Beginning on June 27th, the operational phase will imply the product’s warranty in terms of accuracy, fitness for use or purpose.  Note also the dissemination of Non-Time-Critical (NTC) Sentinel-3A products
  • will begin on June 27th for L2P on AVISO+ dissemination (delivery of cycle 12 on 27th and cycles 13 to 17 during the following week)
  • will be soon disseminated for L3 by CMEMS (delivery of days 2016/12/24 to 2017/01/07)
The L2P STC/NRT products are also available through EUMETSAT dissemination via EumetCast.              
Categories: Climate Science News

12-18 June, 2017 week

AVISO Climate Change News - Thu, 2017-06-22 05:28
Coopération spatiale entre la France et les Etats-Unis Le CNES signe avec la NASA une déclaration sur Mars et l’océanographie (CNES, 2017/06/19)
Animaux & satellites : main dans la main pour observer l'océan austral (CNES, 2017/06/19)
Les insectes, la nouvelle menace en Antarctique ? (Le Point, 2017/06/18)
Impact d’une fonte accélérée de la calotte groenlandaise sur les mouvements migratoires au Sahel (INSU, 2017/06/09)
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Categories: Climate Science News

Campaign in the Lower Seine valley with GPS carpet/ Drone / Lidar

AVISO Climate Change News - Thu, 2017-06-22 03:03
The SWOT (Surface Water and Ocean Topography) mission, result of a Franco-American cooperation (CNES / NASA, with the participation of CSA and UKSA), will measure rivers, lakes and coastal and estuarine area water heights (and their spatial and temporal variations), using a new technical concept: interferometric altimetry. In 2021, after the launch, the performance of SWOT will have to be calibrated and validated thanks to the contribution of other space missions, to available in-situ data, but also by dedicated means deployed on site during the overflight of the satellite in order to have co-temporal measurements. These means must be able to be deployed in remote sites in order to have ground truths on non-instrumented sites, so they must be light.

The GPS carpet in tow of the boat, and the Lidar



Among the various means envisaged to validate the SWOT measurements, the water height information derived from the GPS measurements on a specific buoy and / or the airborne Lidar and / or drone data are the most promising. In this context, CNES has asked its partners (IRD, INSU, CNRS, CLS, etc.) to develop resources that would be implemented during the Cal / Val phase in orbit in 2021. These resources have been developed and a test on the Seine estuary will take place on 22 and 23 June 2017 in order to validate the behavior of the different vectors.

The estuary of the Seine has been retained as a test zone because of the knowledge of this area and the availability of technical means by the “Continental and Coastal Morphodynamics” UMR CNRS 6143 team (M2C). Moreover, the monitoring of the water levels along the estuary by the tide gauges of the Grand Maritime Port of Rouen will provide an independent ground truth.

The CalNaGeo GPS data carpet produced by the Technical Division of the National Institute for the Sciences of the Universe (DT-INSU) in 2016 follows similar developments in the past for the validation of oceanographic measurements for the Jason-2 and 3 missions. The new design of the GPS carpet has been adapted to the problems of continental hydrology. It will be towed by a boat, the "MONOD-ROUEN" of the M2C laboratory.

A light weight altimeter was developed by engineers of the Collecte Localisation Satellites (CLS) company early 2017 to be embarked on a drone. It uses a lidar technology. The drone should follow the boat in order to compare the altimeter performance with those of the GPS carpet. It should fly in the wake of the boat, just in front of the GPS (about 30 m behind the boat, depending on the wake). The drone flies at 30 m altitude and two people (a telepilot and an operator) are planned on the boat to ensure its control. The drone has an automatic pilot with detection and avoidance of possible obstacles (bridges, electrical wires), the pilot being present on boat to take control in case of an incident.

At the same time lidar surveys will be carried out. The LIDAR instrument of the M2C laboratory will be onboard an aircraft that will fly over the lower Seine valley during the two-day campaign. These surveys will be carried out within the framework of the COTEST project coordinated by the M2C laboratory and supported by the CNES TOSCA program.

Categories: Climate Science News

Special Issue of Remote Sensing, "Satellite Altimetry for Earth Sciences" in preparation

AVISO Climate Change News - Wed, 2017-06-21 07:41
Satellite altimetry was initially designed for measuring the ocean’s topography, with reference to an ellipsoid, and for the determination of the marine geoid. Satellite altimetry has provided extremely valuable information on ocean science (e.g., circulation surface geostrophic currents, eddy structures, wave heights, and the propagation of oceanic Kelvin and Rossby waves). With more than 25 years of observations, it is also becoming vital to climate research, providing accurate measurements of sea level variations from regional to global scales. Altimetry has also demonstrated a strong potential for geophysical, cryospheric and hydrological research, and is now commonly used for the monitoring of Arctic and Antarctic ice shet topography, and of terrestrial surface water levels.

A Special Issue of Remote Sensing, "Satellite Altimetry for Earth Sciences" is in preparation. It aims to present reviews and recent advances of general interest in the use of radar altimetry in Earth sciences. Manuscripts can be related to any aspect of radar altimetry technique or geophysical applications. Manuscript resulting from application of new altimetric technology (SAR, SARin and Ka band) and improvements expected from missions to launched in the close future (i.e., SWOT) are also encouraged.
Contributions can be either a review paper on some specific topics, or an original research in this area. For more information about the Special Issue, please see:
  • http://www.mdpi.com/journal/remotesensing/special_issues/SA
Categories: Climate Science News

[L2P Sentinel-3A] : maintenance of the L2P software on June 19th

AVISO Climate Change News - Thu, 2017-06-15 01:46
Due to a software maintenance, the delay delivery of L2P STC and NRT will be disrupted on June 19th...
Categories: Climate Science News

5-11 June, 2017 week

AVISO Climate Change News - Thu, 2017-06-15 00:48
Impact d’une fonte accélérée de la calotte groenlandaise sur les mouvements migratoires au Sahel (INSU, 2017/06/09)
Les océans, un gage pour l’avenir de la planète (Libération, 2017/06/08)
L’océan mondial, pollué par les déchets plastiques! (Natura Sciences, 2017/06/08)
Finding new homes won't help emperor penguins cope with climate change (Science Daily, 2016/06/07)
On line availability of articles depends on the Newspaper/magazine. We can't thus certify that above articles will be freely and permanently available.

Categories: Climate Science News
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