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Landsat Science

Landsat Science
Related:  climat

lapse: Landsat Satellite Images of Climate Change, via Google Earth Engine TIME and Space | By Jeffrey Kluger Spacecraft and telescopes are not built by people interested in what’s going on at home. Rockets fly in one direction: up. That changed when NASA created the Landsat program, a series of satellites that would perpetually orbit our planet, looking not out but down. Over here is Dubai, growing from sparse desert metropolis to modern, sprawling megalopolis. It took the folks at Google to upgrade these choppy visual sequences from crude flip-book quality to true video footage. These Timelapse pictures tell the pretty and not-so-pretty story of a finite planet and how its residents are treating it — razing even as we build, destroying even as we preserve. Chapter 1: Satellite Story | By Jeffrey Kluger It’s a safe bet that few people who have grown up in the Google era have ever heard of Stewart Udall. But in 1966, Udall and his staff had an idea. Since NASA launched the first Landsat satellite in 1972, the program has been in constant operation. 1 of 20

40 Maps That Will Help You Make Sense of the World If you’re a visual learner like myself, then you know maps, charts and infographics can really help bring data and information to life. Maps can make a point resonate with readers and this collection aims to do just that. Hopefully some of these maps will surprise you and you’ll learn something new. If you enjoy this collection of maps, the Sifter highly recommends the r/MapPorn sub reddit. 1. 2. 3. 4. Pangea was a supercontinent that existed during the late Paleozoic and early Mesozoic eras, forming about 300 million years ago. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 37. 38. 39. 40. *Bonus* World Map Tattoo with Countries Visited Coloured

2013/05/03 > BE Belgique 73 > Les variations climatiques des 2000 dernières années ne sont pas les mêmes selon les régions du monde PhysiqueLes variations climatiques des 2000 dernières années ne sont pas les mêmes selon les régions du monde Les variations climatiques des 2000 dernières années présentent des différences régionales marquées. C'est ce que démontre une vaste étude internationale à laquelle l'UCL est associée, qui a reconstruit précisément les températures passées au cours des 2000 dernières années à l'échelle des différents continents. L'une des principales découverte est un refroidissement graduel, observé de manière cohérente sur les différents continents au cours des derniers 2000 ans. Ce lent refroidissement est dû à la superposition de différents facteurs naturels (lentes variations de l'orbite terrestre, activité solaire, volcanisme, etc..). L'organisation PAGES a été fondée en 1991. Les résultats montrent que l'évolution des températures a été plus cohérente parmi les continents de chaque hémisphère qu'entre les deux hémisphères.

David Rumsey Historical Map Collection | The Collection Global Warming and Climate Change skepticism examined United States Digital Map Library - Home Welcome to our website! The United States Digital Map Library is a USGenWeb Archives project, developed in April of 1999 under the coordination of Fred Smoot. The current Coordinator is Adrian Williams. The VolunteersThis project and its all-volunteer staff are dedicated to free, online access for the general public. Our Collection US MapsThis section includes maps of national interest. State and County MapsRepresenting the bulk of our collection, the State and County section includes maps from all 50 US states and oftentimes maps of individual counties in a state. Indian Land CessionsThis collection provides maps of the land cessions made by American Indian Nations during the interval between the formal establishment of the United States and 1894.

DEOS: Current velocities of the Gulf Stream Last updated automagically: Saturday 7 November 2015 21:58:42 CET Since 21 December 2004 the velocity maps show the absolute in stead of relative velocities. This means that the velocities now include the mean Gulf Stream current, based on the CMDT-RIO04 dynamic topography solution by Rio and Hernandez. Starting on 10 January 2005 data from four altimeter satellites (Envisat, Jason-1, TOPEX/Poseidon, GFO) are included in the generations of the Gulf Stream velocity maps. At the same time the area was extended 10 degrees towards the east and results of the last four weeks are presented. All previous maps are reprocessed with the data of all four altimeters inside the new extended region. Current status of the Gulf Stream Relative Gulf Stream velocity fields are derived from near-realtime data from the radar altimeters of the satellites Envisat, Jason-1, and Jason-2. This page presents four maps of current velocities of the Gulf Stream in the vicinity of the East coast of North-America.

Factsheets : Global Positioning Systems Directorate The Global Positioning Systems Directorate is a joint service effort directed by the United States Air Force and managed at the Space and Missile Systems Center, Air Force Space Command, Los Angeles Air Force Base, Calif. The directorate is the Department of Defense acquisition office for developing and producing Global Positioning System (GPS) satellites, ground systems and military user equipment. GPS is a space-based dual use radio navigation system nominally consisting of a minimum of 24-satellite constellation that provides positioning, velocity and timing to military and civilian users worldwide. GPS satellites, in one of six medium earth orbits, circle the earth every 12 hours transmitting continuous ranging signals. In addition to the satellites, the system consists of a worldwide satellite control network and GPS receiver units that acquire the satellite's signals and compute navigation solutions to provide positioning, velocity and timing to the user. Related fact sheets:

Pourquoi Etats-Unis et Chine s'attaquent aux super gaz à effet de serre HFC Le | • Mis à jour le | Par Audrey Garric Lors de leur sommet en "manches de chemise" en Californie, le président américain Barack Obama et le président chinois Xi Jinping n'ont pas seulement abordé les questions risquées comme la cybersécurité, le libre échange et les tensions militaires dans le Pacifique. Ils ont aussi réussi à trouver un terrain d'entente dans un domaine : la lutte contre le changement climatique. Les deux pays ont ainsi annoncé un accord visant à éliminer progressivement la production et l'usage des hydrofluorocarbures (HFC), des gaz industriels considérés comme des "super" gaz à effet de serre. Lire : La Chine et les Etats-Unis concluent un accord contre le changement climatique Les HFC, principaux représentants de la famille des gaz fluorés, sont utilisés dans la réfrigération, la climatisation, ainsi que dans les équipements électriques, les mousses isolantes ou les bombes aérosols. Reste la question de trouver des substituts aussi efficaces et rentables.