Jean-Louis Etienne
 
 
 
Jean-Louis Etienne - Alone on Ice pack
How man copes with the cold
 
Communications - Safety - Emergency assistance
 
Jean-Louis Etienne - Atmosphere & weather
The earth’s atmosphere  
 
Weather forecasting and modeling  
 
The climate and the north pole  
 
The solar energy balance  
 
The greenhouse effect  
 
Jean-Louis Etienne - Arctic ice
The ice pack: frozen saltwater  
 
Ice pack observation satellites  
 
Icebergs : frozen seawater  
 
The arctic ice: climate archives  
 
Ice ages and landscapes  
 
Jean-Louis Etienne - The ocean and marine life
The Arctic Ocean and the ocean currents  
 
Genesis of the arctic ocean  
 
Arctic plankton  
 
Oceanic biodiversity and the food chain  
 
Whales and other cetaceans  
 
Seals and walruses  
 
Jean-Louis Etienne - Life on land
Arctic flora  
 
Arctic fauna  
 
Polar bears  
 
Birds of the arctic  
 
Evolution of species and climate  
 
Jean-Louis Etienne - History and geography
Geography of the Arctic regions  
 
Geographic North Pole and magnetic North Pole  
 
Who owns the arctic ?  
 
Exploring the deep north  
 
The Inuit people  
 
The other peoples of the deep North  
 
The Arctic today  
 
Jean-Louis Etienne - Man's impact
Man and arctic biodiversity  
 
Pollution in the arctic  
 
Climate warming: the natural cycles  
 
The increase in the greenhouse effect  
 
The impact of global warming  
 
 
 
Atmosphere and weather
Weather forecasting and modeling
 
 

What’s the weather tomorrow ?
Meteorologists are getting better and better at answering this question, but forecasting more than 5 days ahead is still very uncertain. This is because the Earth’s climate is such a complex overall system: each cloud, each storm, each plot of farmland, each built-up area, each ocean current (even down deep) and each stretch of polar pack ice affects our climate. And no-one can know what’s going on all over the globe, from pole to Equator… It is possible to forecast seasonal trends, but no-one can say what the weather will be like in 2 weeks time on a particular beach.

A worldwide observation network
Dotted across all the continents on Earth there is a network of thousands of weather observation stations recording measurements such as temperature, wind speed, pressure, humidity, etc. Aircraft and weather balloons are used to take measurements at altitude, while ships and weather buoys send back the same data, plus information on ocean currents. All this data is fed into computers used to draw up weather forecasts.

Weather satellites too
Even out in space, weather satellites orbit the Earth in mobile and geo-stationary satellites orbit (geo-stationary satellites orbit at the same speed as the Earth’s rotation, so they remain above a fixed spot) the globe sending back real-time images of atmospheric conditions. This constantly updated overall picture, combined with data from surface facilities, has been a big factor in improving weather forecasting.

More reliable weather models
The computers used by meteorologists draw up forecasts according to predetermined methods and using parameters already implanted in their memory. In order to simulate the circulation of the various earthly fluids, the atmosphere and the oceans are cut up into compartments and the computer calculates the impact of each one on the adjacent compartments. But when calculating forecasts several hours ahead, any variation in the initial stages can produce a totally different result. The only solution here is to fine-tune the compartments to factor in the influence of landscape relief, living organisms etc., and to develop even more powerful “number-crunchers”.

 
Atmosphere & weather
 
 
 
 
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