organization:european geosciences union

OSIRIS catches activity in the act
▻http://blogs.esa.int/rosetta/2015/04/20/osiris-catches-activity-in-the-act

Rosetta’s scientific imaging system OSIRIS has witnessed a new jet of dust emerging from the surface of #Comet_67P/Churyumov-Gerasimenko. The image was presented during the European Geosciences Union General Assembly, EGU, in Vienna last week. Sometimes it is all a matter of being in the right place at the right time. Or, as in the case of ESA’s space probe #Rosetta, of opening your eyes at the exactly right moment. In mid-March, the OSIRIS camera was able to catch the elusive moment when a new dust jet from #comet 67P/C-G burst into life. The comet’s activity has been significantly increasing over the last weeks and months. As the comet moves closer to the Sun along its orbit, its nucleus gets warmer and warmer. Frozen gases sublimate from its surface, carrying dust particles with it and (...)

#CometWatch #Images #Science ##CometWatch #instruments #rosetta #science

COSIMA: Meet the family
▻http://blogs.esa.int/rosetta/2015/04/16/cosima-meet-the-family

Rosetta’s dust analysing instrument COSIMA (COmetary Secondary Ion Mass Analyser) has been very busy collecting dust – 12,000 grains and counting! The COSIMA team shared this image of some of their named dust grains at the European Geosciences Union General Assembly in Vienna this week. The 12,000 grains were collected between 11 August 2014 and 28 March 2015, on nine target plates measuring one square centimetre each. The image presented here represents one of these targets, and shows grains collected up to 12 December 2014. COSIMA studies dust in situ by capturing grains on small target plates like this one, first imaging these with an optical microscope and then analysing the composition of selected grains using a secondary ion mass spectrometer. COSIMA has 74 target plates in total (...)

#Comet_67P #Images #Instruments #Rosetta #Science #rosetta #science

#Rosetta at EGU – press briefing 14 April
▻http://blogs.esa.int/rosetta/2015/04/13/rosetta-at-egu-press-briefing-14-april

Rosetta mission scientists are meeting this week in Vienna, Austria, for the annual European Geosciences Union General Assembly, EGU. A press briefing will be held on Tuesday 14 April at 12:00 CEST, to report on the latest #Science results from the mission. Watch live, here. More information about the Rosetta science sessions can be found here. 

Megacities contend with sinking land
▻http://www.bbc.co.uk/news/science-environment-27202192

http://news.bbcimg.co.uk/media/images/74514000/jpg/_74514460_74514459.jpg

In some parts of the globe, the ground is going down 10 times faster than the water is rising, with the causes very often being driven by human activity.

Decades of ground water extraction saw Tokyo descend two metres before the practice was stopped.

Speaking at the European Geosciences Union General Assembly, researchers said other cities must follow suit.

#villes #subsidence #sols #eau #climat

Press Release: Geoengineering approaches to reduce climate change unlikely to succeed
▻http://www.egu.eu/news/88/geoengineering-approaches-to-reduce-climate-change-unlikely-to-succeed

Reducing the amount of sunlight reaching the planet’s surface by geoengineering may not undo climate change after all. Two German researchers used a simple energy balance analysis to explain how the Earth’s water cycle responds differently to heating by sunlight than it does to warming due to a stronger atmospheric greenhouse effect. Further, they show that this difference implies that reflecting sunlight to reduce temperatures may have unwanted effects on the Earth’s rainfall patterns. The results are now published in Earth System Dynamics, an open access journal of the European Geosciences Union (EGU).

#géoingénierie #climat