Climate Science News

5 March - 11 March 2018 week

AVISO Climate Change News - Thu, 2018-03-15 07:52
Les scientifiques prévoient une hausse de plus de 2°C dans 13 villes (Challenges, 07/03/2018) Un océan de plastique filmé en Indonésie (Le Point, 07/03/2018) Desertification and monsoon climate change linked to shifts in ice volume and sea level (07/03/2018) Des mammouths dans le permafrost de Sibérie (RTS, 07/03/2018) 2 zones suspectes et beaucoup d'incertitudes dans l'océan indien sud-ouest (Cyclone Ocean Indien, 10/03/2018) Global fisheries to be, on average, 20 percent less productive in 2300, UCI study finds (Science Daily, 08/03/2018) 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

26 February - 4 March 2018 week

AVISO Climate Change News - Fri, 2018-03-09 01:13
Probabilité de cyclogenèse en augmentation dans l'océan indien (Cyclone Ocean Indien, 26/02/18) 70 % des manchots royaux sont menacés de disparaître d’ici à la fin du siècle (Le Monde, 26/02/18) L’Antarctique, laboratoire du changement climatique (Capital, 01/03/18) Norvège: le grenier de l'humanité s'adapte pour lutter contre le réchauffement climatique (Le Figaro, 02/03/18) Tuvalu, l'île qui prend sa revanche sur le réchauffement climatique (7sur7, 04/03/18) Antarctique : des scientifiques ont découvert des glaces vieilles de 1.5 million d’années (Fredzone, 04/03/18) 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

Maintenance in progress on CNES FTP server

AVISO Climate Change News - Thu, 2018-03-08 02:11
The maintenance on the CNES FTP Server is on progress. We apologize the inconvenience
Categories: Climate Science News

March 2018: flash flood at the Têt river mouth

AVISO Climate Change News - Wed, 2018-03-07 01:19
SWOT will provide with high resolution coastal and inland measurements over rivers. They will help...
Categories: Climate Science News

[JASON-2] Restarted successfully

AVISO Climate Change News - Wed, 2018-03-07 00:54
As announced last week, Jason-2 was restarted successfully on Friday March 2nd around 10:00UTC.
The satellite status was checked, and its behavior is fully nominal at this time. OGDR production was restarted on 2018/03/05 after the pass at 15:45UTC (i.e. cycle #524 – Pass#45). The distribution of IGDR (i.e. cycle #524– Pass#215) has been authorized after altimeter  experts validation  on 2018/03/06. 
Categories: Climate Science News

A warm approach to the equinox

NSIDC Artic Sea Ice News - Tue, 2018-03-06 09:00

As temperatures at the North Pole approached the melting point at the end of February, Arctic sea ice extent tracked at record low levels for this time of year. Extent was low on both the Atlantic and Pacific sides of the Arctic, with open water areas expanding rapidly in the Bering Sea during the latter half of the month. On the other side of the globe, Antarctic sea ice has reached its minimum extent for the year, the second lowest in the satellite record.

Overview of conditions Figure 1. Arctic sea ice extent for February 2018 was 13.95 million square kilometers (5.39 million square miles). The magenta line shows the 1981 to 2010 average extent for that month.

Figure 1. Arctic sea ice extent for February 2018 was 13.95 million square kilometers (5.39 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

Winter continues to be mild over the Arctic Ocean. Sea ice extent remained at record low daily levels for the month. Arctic sea ice extent for February 2018 averaged 13.95 million square kilometers (5.39 million square miles). This is the lowest monthly average  recorded for February, 1.35 million square kilometers (521,000 square miles) below the 1981 to 2010 average and 160,000 square kilometers (62,000) below the previous record low monthly average in 2017.

Extent was especially low in the Bering Sea where sea ice declined during the first three weeks of the month. The eastern part of the Bering Sea was largely ice-free for most of the month; extent was low on the western side, with the ice edge further north than normal. In the Chukchi Sea, extent also retreated during part of February, with open water developing north of the Bering Strait on both the Siberian and Alaskan coasts. As seen all winter, ice extent continued to be below average in the Barents Sea, and at the end of February, a wedge of open water formed north of Svalbard that extended well into the Arctic Ocean.

Conditions in context

Figure 2a. The graph above shows Arctic sea ice extent as of March 4, 2018, along with daily ice extent data for four previous years. 2017 to 2018 is shown in blue, 2016 to 2017 in green, 2015 to 2016 in orange, 2014 to 2015 in brown, 2013 to 2014 in purple, and 2011 to 2012 in dotted brown. 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 plot shows the average sea level pressures at the 925 hPa level for February 2018. Yellows and reds indicate higher than average air pressures; blues and purples indicate lower than average air pressures.

Figure 2b. This plot shows the average sea level pressures at the 925 hPa level for February 2018. Yellows and reds indicate higher than average air pressures; blues and purples indicate lower than average air pressures.

Credit: NSIDC courtesy NOAA Earth System Research Laboratory Physical Sciences Division
High-resolution image

Figure 2c. This figure shows differences from the average in temperature in degrees Celsius and in addition to wind conditions for the period February 22 to 26, 2018. In addition, the North Atlantic Oscillation (NAO) index is shown in the lower left. This is a measure of the strength of the westerly winds in the North Atlantic. When the index is negative, the flow is wavier, which increases the probability of transport of warm air to Greenland from the south.

Figure 2c. This figure shows differences from average temperature in degrees Celsius, and wind conditions for the period February 22 to 26, 2018. In addition, the North Atlantic Oscillation (NAO) index is shown in the lower left. This is a measure of the strength of the westerly winds in the North Atlantic. When the index is negative, the flow is wavier, which increases the probability of transport of warm air to Greenland from the south.

Credit: European Centre for Medium-Range Weather Forecasts (ECMWF) IFS forecast model
High-resolution image

Low pressure centered just east of the Kamchatka Peninsula and high pressure centered over Alaska and the Yukon during February set up southerly winds that brought warm air and warm ocean waters into the Pacific side of the Arctic Ocean, impeding southward ice growth. This helps to explain the rapid loss of ice extent in the Bering Sea and the ice-free regions within the Chukchi Sea during the month. The warm air intrusion is evident in the 925 mb air temperatures, with monthly temperatures 10 to 12 degrees Celsius (18 to 22 degrees Fahrenheit) above average in the Chukchi and Bering Sea.

On the Atlantic side, low pressure off the southeast coast of Greenland and high pressure over northern Eurasia helped to funnel warm winds into the region and may have also enhanced the northward transport of oceanic heat. At the end of the month, this atmospheric circulation pattern was particularly strong, associated with a remarkable inflow of warm air from the south, raising the temperatures near the North Pole to above freezing, around 20 to 30 degrees Celsius (36 to 54 degrees Fahrenheit) above average. Air temperatures at Cape Morris Jesup in northern Greenland (83°37’N, 33°22’W) exceeded 0 degrees Celsius for several hours and open water formed to the north of Greenland at the end of the month. This is the third winter in a row in which extreme heat waves have been recorded over the Arctic Ocean. A study published last year by Robert Graham from the Norwegian Polar Institute showed that recent warm winters represent a trend towards increased duration and intensity of winter warming events within the central Arctic. While the Arctic has been relatively warm for this time of year, northern Europe was hit by extreme cold conditions at the end of February.

February 2018 compared to previous years Figure 3. Monthly 2018 ice extent for 1979 to 2018 shows a decline of 3.1 percent per decade.

Figure 3. Monthly 2018 ice extent for 1979 to 2018 shows a decline of 3.1 percent per decade.

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

The linear rate of decline for February is 47,000 square kilometers per year (18,000 square miles per year), or 3.1 percent per decade.

Late freeze-up freeze average and anomaly plots

Figure 4. These graphs show the average Arctic Ocean ice freeze-up dates for 1979 to 2017 (top) and the number of days that freeze-up occurred earlier (cool colors) or later (warm colors) than average (bottom).

Credit: J. Miller, NASA Goddard Space Flight Center
High-resolution image

This year, the freeze-up started earlier than average over much of the central Arctic Ocean, near average within Hudson and Baffin Bays, but significantly later than average elsewhere. Freeze-up was delayed by more than a month later than average within the Chukchi and Bering Seas on the Pacific side, and within the Barents and East Greenland Seas on the Atlantic side. In these regions freeze-up happened after December. Later freeze-up impacts sea ice thickness, reducing the number of days over which sea ice can grow during winter.

Winter navigation in the Arctic without an icebreaker Figure 4. This figure shows the distribution of Arctic sea ice according to stage of development, , as of February 22, 2018. Pink shows new ice; purple shows young ice; blue shows first year thin ice; orange shows first year medium ice, red shows first year thick ice, brown shows old ice, and while shows glacial ice.

Figure 5. This figure shows the distribution of Arctic sea ice according to stage of development, , as of February 22, 2018. Pink shows new ice; purple shows young ice; blue shows first year thin ice; orange shows first year medium ice, red shows first year thick ice, brown shows old ice, and while shows glacial ice.

Credit: U.S. National Ice Center
High-resolution image

The Arctic Ocean is becoming more accessible for shipping. Most of the increase in commercial shipping traffic has been during summer, primarily through the Northern Sea Route along the coast of Siberia. However, this February a commercial tanker, the Eduard Toll, made the first crossing of the Northern Sea Route in winter. Improvements in ship-building and the development of ice-strengthened hull technology is a major factor in enabling winter access. Previous ice-strengthened ships could only navigate safely through 0.5 meter thick ice, compared to the 1.8 meter thick ice that the Eduard Toll cruised through. A fleet of six ships with similar technology is being constructed by a South Korean shipbuilder.

While the Northern Sea Route has tended to be dominated by first-year ice, which typically reaches a maximum of around 2 meters, thicker (3- to 4-meter) multi-year ice would be a hazard even to the newer, stronger ships. According to analysis by the U.S. National Ice Center, this year’s old ice (multi-year ice) has pulled completely away from the coast and the Northern Sea Route is dominated by first-year medium (0.7- to 1.2-meter) or first-year thick (1.2- to 2-meter) ice.

Opposite pole, same near-record low extent Figure 6. The graph above shows Antarctic sea ice extent as of March 1, 2018, along with daily ice extent data for four previous years. 2017 to 2018 is shown in blue, 2016 to 2017 in green, 2015 to 2016 in orange, 2014 to 2015 in brown, 2013 to 2014 in purple, and 2011 to 2012 in dotted magenta. 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 6a. The graph above shows Antarctic sea ice extent as of March 1, 2018, along with daily ice extent data for four previous years. 2017 to 2018 is shown in blue, 2016 to 2017 in green, 2015 to 2016 in orange, 2014 to 2015 in brown, 2013 to 2014 in purple, and 2011 to 2012 in dotted magenta. 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

 National Snow and Ice Data Center|High-resolution image

Figure 6b. This figure shows Antarctic sea ice extent for February 28, 2018. Sea Ice Index data. About the data

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

In the Antarctic, sea ice extent reached its daily seasonal minimum, 2.18 million square kilometers (842,000 square miles), on February 20 and 21. This is the second lowest minimum extent in the satellite record, 70,000 square kilometers (27,000 square miles) above the record low, which was set on March 3, 2017. The February average was 2.29 million square kilometers (884,000 square miles), second lowest in the satellite record, and 20,000 square kilometers (7,700 square miles) above the record low February in 2017.

Sea ice in the Antarctic is highly variable from year to year—much more so than in the Arctic. This is clearly seen in the February extent values, where low 2011 values were followed by record or near-record highs in 2013, 2014, and 2015. This was then followed by record or near-record lows in 2017 and this year.

Sea ice extent is particularly low in the Ross and western Amundsen Sea region, and along the southern reaches of the Bellingshausen Sea. Patchy sea ice areas along the East Antarctic coast are near-average in extent.

Further reading

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., 16, 6974-6983, doi:10.1002/2017GL073395.

Kretschmer, M., D. Coumou, L. Agel, M. Barlow, E. Tziperman, and J. Cohen. 2017. More persistent weak stratospheric polar vortex states linked to cold extremes, Bull. Amer. Meteor. Soc., doi:10.1175/BAMS-D-16-0259.1.

 

 

Categories: Climate Science News

19-25 February 2018 week

AVISO Climate Change News - Thu, 2018-03-01 08:48
Anomalie chaude bien établie sur le bassin sud-ouest de l'océan indien (Cyclone Ocean Indien, 24/02/2018) Le niveau des océans s’élèvera pendant (au moins) 300 ans (Sciencepost, 23/02/2018) Les animaux qui blanchissent l’hiver s’adaptent au réchauffement climatique (Sciences et Avenir, 21/02/2018) Un observatoire spatial du climat pour lutter contre le changement climatique (Futura Sciences, 21/02/2018) East Coast Shatters Temperature Records, Offering Preview to a Warming World (Inside Climate news, 21/02/18)  Scientists race to explore Antarctic marine life revealed by giant iceberg (The Guardian, 20/02/2018) 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

[JASON-2] Status update

AVISO Climate Change News - Thu, 2018-03-01 08:09
Investigations performed since last week show that the safe hold mode triggered on February 20th is again due to the same gyro failure as previously. It has then been decided to restart operations on Jason-2 as soon as possible, using gyrometer #1, which has been inactive since October 2017. The Poseidon Altimeter and all payload instruments will be restarted on March 2nd around 10:00UTC, i.e. on pass 216 of cycle 523. However, in order to take sufficient time to check the quality of the products generated, the first post-SHM OGDRs and IGDRs will only be disseminated on Monday, March, 5th. We will keep you informed of the next events.
Categories: Climate Science News

[SARAL] Happy anniversary to SARAL !

AVISO Climate Change News - Mon, 2018-02-26 02:03
Happy anniversary to SARAL. Five years later it continues a major contribution to Ocean monitoring as well as climate change studies. AltiKa and Argos onboard SARAL are clearly a big achievement and pave the way for future cooperation between ISRO and CNES.

Thank to all the teams who have make this story possible; long life to SARAL...

Categories: Climate Science News

12-18 February 2018 week

AVISO Climate Change News - Fri, 2018-02-23 03:16
La terre risque de devenir un désert en 2050 à cause du réchauffement climatique (Fredzone, 2018/02/18) What is the longest-lived marine mammal? (National Ocean Service, 2018/02/16) L'ONG WWF au secours des phoques de Saaima (France Info, 2018/02/16) L’effondrement brutal de deux glaciers tibétains élucidé (Pour la Science, 2018/02/09) L'Atlantique Nord devient bien plus acide (Le Figaro, 2018/02/12) L'acidification des océans aura des conséquences préoccupantes sur les espèces marines (MaxiSciences, 2018/02/15) 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

[JASON-2] : SATELLITE IN SAFE HOLD MODE SINCE TUESDAY FEBRUARY 20th 18:40:09 UTC

AVISO Climate Change News - Thu, 2018-02-22 07:25
Jason-2 spacecraft entered into safe mode Tuesday, February 20th at 18:40:09 UTC, immediately interrupting its measurements at the end of cycle 522.    The satellite is currently in a safe and stable Sun-pointing configuration. In the same way as during the last 3 SHMs. This interruption is due to the disjunction of a gyro (in this case Gyro 2, which was operating nominally since mid-October). In the future days, the exact status of the platform will be monitored, and the best schedule to resume the mission will be determined to keep users informed of the progress.
Categories: Climate Science News

5-11 February 2018 week

AVISO Climate Change News - Thu, 2018-02-15 02:26
La Nasa a recréé un "Océan extraterrestre" pour tester un nouveau type de submersible (Fredzone, 2018/02/08)
Réchauffement climatique : l'affaire de tous (La Dépêche, 2018/02/09)
Réchauffement : l'océan monte mais... ces atolls s'agrandissent ! (Le dauphine, 2018/02/09)
Raconter le climat, un projet fidjien qui laisse l’UE de marbre (Euractiv, 2018/02/09)
Sea floor uplift after last ice age causes methane release in the Arctic today (Sciencedaily, 2018/02/06)
L’impact du réchauffement climatique sur les ours polaires est pire que ce que l’on estimait (Daily Geek Show, 2018/02/05) 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

SSALTO Ground Segment data delay

AVISO Climate Change News - Mon, 2018-02-12 09:04
Some products have not been delivered this weekend due to a problem on the exchange server. Since this morning the situation has become nominal again.
Categories: Climate Science News

Sea ice tracking low in both hemispheres

NSIDC Artic Sea Ice News - Tue, 2018-02-06 13:40

January of 2018 began and ended with satellite-era record lows in Arctic sea ice extent, resulting in a new record low for the month. Combined with low ice extent in the Antarctic, global sea ice extent is also at a record low.

Overview of conditions sea ice extent map

Figure 1. Arctic sea ice extent for January 2018 was 13.06 million square kilometers (5.04 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

The new year was heralded by a week of record low daily ice extents, with the January average beating out 2017 for a new record low. Ice grew through the month at near-average rates, and in the middle of the month daily extents were higher than for 2017. However, by the end of January, extent was again tracking below 2017. The monthly average extent of 13.06 million square kilometers (5.04 million square miles) was 1.36 million square kilometers (525,000 square miles) below the 1981 to 2010 average, and 110,000 square kilometers (42,500 square miles) below the previous record low monthly average in 2017.

The pattern seen in previous months continued, with below average extent in the Barents and Kara Seas, as well as within the Bering Sea. The ice edge remained nearly constant throughout the month within the Barents Sea, and slightly retreated in the East Greenland Sea. By contrast, extent increased in the Gulf of St. Lawrence, off the coast of Newfoundland, in the eastern Bering Sea and the Sea of Okhotsk. Compared to 2017, at the end of the month, ice was less extensive in the western Bering Sea, the Sea of Okhotsk and north of Svalbard, more extensive in the eastern Bering Sea and in the Gulf of St. Lawrence. Overall, the Arctic gained 1.42 million square kilometers (548,000 square miles) of ice during January 2018.

Conditions in context extent timeseries

Figure 2a. The graph above shows Arctic sea ice extent as of February 5, 2018, along with daily ice extent data for five previous years. 2017 to 2018 is shown in blue, 2016 to 2017 in green, 2015 to 2016 in orange, 2014 to 2015 in brown, 2013 to 2014 in purple, and 2012 to 2013 in dotted brown. 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

airtemp

Figure 2b. The plot shows air temperatures in degrees Celsius in the Arctic as difference from average for January 2018. Yellows, oranges, and reds indicate higher than average temperatures; blues and purples indicate lower than average temperatures.

Credit: NSIDC courtesy NOAA/ESRL Physical Sciences Division
High-resolution image

Air temperatures at the 925 hPa level (about 2,500 feet above sea level) remained unusually high over the Arctic Ocean (Figure 2b). Nearly all of the region was at least 3 degrees Celsius (5 degrees Fahrenheit) or more above average. The largest departures from average of more than 9 degrees Celsius (16 degrees Fahrenheit) were over the Kara and Barents Seas, centered near Svalbard. On the Pacific side, air temperatures were about 5 degrees Celsius (9 degrees Fahrenheit) above average. By contrast, 925 hPa temperatures over Siberia were up to 4 degrees Celsius (7 degrees Fahrenheit) below average. The warmth over the Arctic Ocean appears to result partly from a pattern of atmospheric circulation bringing in southerly air, and partly from the release of heat into the atmosphere from open water areas. Sea level pressure was higher than average over the central Arctic Ocean, stretching towards Siberia. This pattern, coupled with below average sea level pressure over the Chukchi and Bering seas, helped to move warm air from Eurasia over the central Arctic Ocean.

Ice growth for January averaged 37,000 square kilometers (14,000 square miles) per day, close to the average rate for the month of 42,700 square kilometers per day (16,486 square miles per day). In the Barents Sea, the ice extent was the second lowest during the satellite data record. Ice conditions in this region of the Arctic are increasingly viewed as important in having downstream effects on atmospheric circulation. These proposed links include northward expansion of the Siberian High and cooling over northern Eurasia.

January 2018 compared to previous years extent trend graph

Figure 3. Monthly January ice extent for 1979 to 2018 shows a decline of 3.3 percent per decade.

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

The linear rate of decline for January is 47,700 square kilometers (18,400 square miles) per year, or 3.3 percent per decade.

Engaging stakeholders in sea ice forecasting tourism graphs

Figure 4. These graphs show changes in polar tourism based on membership in the Association of Arctic Expedition Cruise Operators (AECO, top), and by the number and type of Arctic vessels operated or managed (bottom).

Credit: Kelvin Murray, Director, Expedition Operations EYOS Expeditions
High-resolution image

Uncertainty about future sea ice conditions presents challenges to industry, policymakers, and planners responsible for economic, safety, and risk mitigation decisions. The ability to accurately forecast the extent and duration of sea ice on different timescales is relevant to a wide range of Arctic maritime activities. While there have been considerable advances in sea ice forecasting over the past decade, it remains unclear how well end users are able to utilize these products and services in their planning. In response, the Sea Ice Prediction Network, in collaboration with several sponsors, held a workshop at the Arctic Frontiers Conference in Tromsø, Norway to foster dialogue between stakeholders and sea ice forecasters.

Conference attendees recognized that the sea ice forecasting community and users of these forecasts need a common language. Often forecast users do not understand the data presented by forecasters, nor do they have the skills to interpret the complex data products. Most marine operators in the Arctic require accurate daily to short-term (< 72 hours) information on the sea ice edge and near-ice-edge concentration. Forecast users often want additional information such as ice strength, ice thickness and ice drift. These data need to be accessed in a user-friendly format that can be easily downloaded (e.g., to a ship at sea). Typically, ice charts from national ice centers or high-resolution Synthetic Aperture Radar image maps are used for describing and analyzing sea ice for real-time navigation.

Longer-term seasonal ice forecasts are potentially useful to the polar marine industry but are not yet being relied upon. While improving, the uncertainty in these forecasts has not been clearly communicated. Nevertheless, logistics planners are interested in using longer-term forecasts, mostly to augment or extend more timely data or in-house diagnostics. Tour operators in particular desire seasonal and even two- to three-year forecasts so that they can plan what to offer their customers. Along with the increase in polar tourism (Figure 4), there is also significant industry traffic in the European Arctic, the Northwest Passage and some areas in the Northern Sea Route. Due to the decreasing ice cover, we can expect an extension of the seasonal activity, with ships embarking earlier and ending their journeys later than in previous years. This underscores the need for accurate forecasting, extending to the more variable shoulder seasons of Arctic sea ice.

Importance of ice drift

Figure 5. The top figure shows the location of the R/V Lance during the N-ICE2015 expedition (pink lines) with aircraft flight lines shown in black and blue. The bottom figure shows a time series of wind speed and direction, together with rates of ice divergence (blue line) and shear (purple line). Figure from Itkin et al. 2017.

Credit: Norwegian Polar Institute
High-resolution image

As the Arctic sea ice cover continues to thin, convergent sea ice motion can more readily pile up ice into large ridges. Such ridges can be hazardous to marine activities in the Arctic. Divergent ice motion produces openings in the ice called leads, where new ice can readily grow. Winds are the main driver for both ridging and lead formation. A single storm event can lead to significant redistribution of sea ice mass through ridging and new leads. As part of the Norwegian Young Sea ICE (N-ICE2015) expedition, colleagues at the Norwegian Polar Institute made detailed sea ice thickness and ice drift observations before and after a storm in an area north of Svalbard (Figure 5). Results showed that about 1.3 percent of the level sea ice volume was pressed together into ridges. Combined with new ice formation in leads, the overall ice volume increased by 0.5 percent. While this is a small number, sea ice in the North Atlantic is typically impacted by 10 to 20 storms each winter, which could account for 5 to 10 percent of ice volume each year.

Antarctic sea ice also low, leading to low global sea ice extent

In the Southern Hemisphere, after January 11 sea ice began tracking low, leading to a January average extent that was the second lowest on record. The lowest extent for this time of year was in 2017. Extent is below average in the Ross Sea and the West Amundsen Seas, while elsewhere extent remains close to average. The low ice extent is puzzling, given that air temperatures at the 925 hPa level are near average or below average (relative to the 1981 to 2010 period) over much of the Southern Ocean. The Weddell and Amundsen Seas were 1 to 2 degrees Celsius (2 to 4 degrees Fahrenheit) below average. Slightly above-average temperatures were the rule in the northwestern Ross Sea.

Further reading

Itkin, P., Spreen, G., Hvidegaard, S. M., Skourup, H., Wilkinson, J., Gerland, S., & Granskog, M. A. 2018. Contribution of deformation to sea ice mass balance: A case study from an N-ICE2015 storm. Geophysical Research Letters, 45. https://doi.org/10.1002/2017GL076056.

 

Categories: Climate Science News

29 January - 4 February, 2018 week

AVISO Climate Change News - Tue, 2018-02-06 08:06
Inondations. Et si le réchauffement climatique était responsable ? (Ouest France, 2018/02/04) Réchauffement climatique : le littoral européen menacé par la montée des eaux (Euronews, 2018/02/02) Réchauffement climatique: L'ours polaire ne trouve plus assez de phoques pour se nourrir (20 minutes, 2018/02/02) Sentinel-3B good to go (ESA, 2018/02/02) Acidité des océans : quel sera l'impact de variations saisonnières plus marquées ? (INSU, 2018/01/30) En 2017, nos océans n’ont jamais été aussi chauds (rse.net, 2018/01/30) 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

21-28 January 2018 week

AVISO Climate Change News - Thu, 2018-02-01 06:23
Les océans contenaient de l’oxygène 250 millions d’années avant l’atmosphère ! (Science post, 2018/01/29) Savoirs pour tous : niveau de la mer et réchauffement climatique (Tahiti info, 2018/01/26) Climat : la chaude année 2017 en graphiques (Le Monde, 2018/01/20) Alerte sur l'océan : la fréquence du blanchissement des récifs coralliens s’accélère (Sud Ouest, 2018/01/20) 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

Feeling the heat

NASA Climate News - Fri, 2012-09-14 00:09
A former intern tells why she?s returned to JPL
Categories: Climate Science News

Grace mission offers a novel view of Earth?s water supplies

NASA Climate News - Thu, 2012-09-13 02:09
The Grace mission offers a novel and much needed view of Earth?s water supplies.
Categories: Climate Science News
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