Researchers at the science of Earth Observation (EOS) group based at the Center for Space Research at the University of Leicester have published satellite images of the United Kingdom for a week in which most areas have been covered by snow.

The images were captured by the Advanced Along-Track Scanning Radiometer (AATSR) on board the ENVISAT satellite of ESA 7 and January 8. AATSR is a double view, multi-channel, Radiometer Imager 1 km spatial resolution and a swath width of 512 km.

The AATSR is funded by the Department of Energy and Climate Change (and previously funded by the Ministry of Food, Rural Affairs and Environment) with the platform and processing of data provided by the European Space Agency.

In both images, the snow can be seen lying in most places in the UK, with major cities like departing shadows on the white snow. On January 7, West of Ireland was free of snow, which reflects the position of the warmer air to the west over the Atlantic – the air was blocked by the cold air on the United Kingdom. On January 8, clouds bringing snow showers after many eastern regions, including Leicester, can be seen – the shadow of these clouds are also visible. Unaffected areas and regions where the melting occurred are indicated by red colors are especially visible in the coastal areas in the south and west due to the warming influence of the Atlantic Ocean Current . These powerful images show clearly the usefulness of satellite Earth observation for monitoring such events.

Dr John Remedios, Head of the EOS Group, University of Leicester, said:

“These are wonderful images produced by an instrument of first class United Kingdom. They illustrate how the landscape of the entire country can be significantly altered by changes in the circulation of the atmosphere. It is particularly struck by the contrast between UK and Ireland’s west end, where the air was warmer. The changes in the boundaries between the hot air from the Atlantic and the cold polar air have a strong impact on the practical and economic life of the United Kingdom, as we have seen in recent weeks. We will use the AATSR images to examine the pattern of cold temperatures in the United Kingdom so that we can study in more detail what were the areas most affected by the cold wave. ”

According to Philip Eden, Vice President of the Royal Meteorological Society, he was the longest spell of frost across the United Kingdom since the mid 80s. The immediate drivers for the weather extremes are:

* The dominant weather systems (synoptic situation): The cold weather was the result of a “blocking” of high pressure which prevented milder Atlantic air to travel through the United Kingdom causing air cold to be fed by Arctic weather systems moved in any North-East bringing moist air to England.
* The strength and position of the Polar Front Jet Stream: This is the narrow, fast-flowing, conveyor belt winds in the upper atmosphere that drive weather systems across the Atlantic – these systems provide weather for the United Kingdom. They are formed by differences in temperature between the cold polar air and warm tropical air and are usually high at this time of year, forcing a series of depressions (systems that bring unsettled weather conditions) on the United Kingdom . However, the jet stream is relatively low at the moment, very winding as it flows from west to east (from the tropics to the poles and the tropics) – in early January, the United Kingdom has happened d ‘be on the side of “cold” this treadmill. Therefore, while the Atlantic depressions are forced down in Portugal and the Mediterranean, north-east winds were cold food to the United Kingdom, the Arctic and Russia.

The fluctuation of global climate anomalies, which describe changes in patterns of atmospheric pressure in May to provide additional explanations:

* Arctic Oscillation (AO): The OC refers to changes in the strength of atmospheric pressure (measured at sea level) in the Arctic and middle latitudes. He is currently in an extremely negative – above normal pressure over the polar regions and below normal pressure over the middle latitudes. The resulting pressure differences smaller and weaker of these systems allow cold air southward. This current of cold air caused by winter weather in northern Europe.
* North Atlantic Oscillation (NAO): The NAO is the difference in pressure between the Iceland low and Azores high, and is closely linked to the AO. The NAO also currently in a negative phase (above normal pressure on Iceland, below normal pressure over the Azores). In Northern Europe it is usually associated with temperatures below normal in most of the precipitation below normal, as are removed from the west.
* El Niño-Southern Oscillation (ENSO) is the cyclic (3-7) Pacific Ocean phenomenon in which the trade winds diminish and sometimes reverse, causing warm air rises in the east Pacific, amending global weather patterns. This may change the strength and position of jet stream in the northern hemisphere, move south on the United Kingdom, favoring an increase in precipitation, but which usually brings milder and humid to England.

‘Teleconnections “- relationships between climatic anomalies widely in different parts of world and regional weather patterns – are natural aspects of the chaotic atmosphere. They are well documented in many parts of the world and are constantly monitored to better understand and improve climate forecasts.

In reality, the recent weather extremes are likely to arise from a combination of factors, and is certainly not evidence that “climate change” has left – so every year, regional anomalies are intrinsic, it long – term global trend which is important when assessing climate change. The recent extreme weather conditions, however, remind us clearly that global warming does not mean the end of the cold weather events!