Posted by Art Of Legend India [dot] Com On 10:41 PM
Summary: We examine some of the scientific causes of extreme weather and what it has done to our planet over the years.
The world at large, and especially UK, has been witnessing crazy weather in recent years. Extreme heat waves, with temperatures to all-time highs, occur alongside storms, and heavy rainfall. There have always been such extreme weather events. However, while such extreme events were a rarity in the past, they have started to recur very frequently now.
A major cause for the increasing recurrence of extreme weather is global warming. Global temperatures have risen 0.5°C (0.9°F) a year, on average, since 1970. This is primarily owing to the presence of greenhouse gases in the atmosphere.
The additional heat in the atmosphere has increased the incidence of extreme heat waves, and droughts.
The increasing temperature warms up the ocean more, and results in more moisture evaporating into the atmosphere. There is an increase of about four percent of moisture in the air now, compared to 1970. This causes heavy and intense rainfall, at times accompanied by flash floods. The extra water vapour in the atmosphere make hurricanes, typhoons, and other storms stronger, more buoyant, more powerful, and more long-lasting.
One big casualty of the soaring temperature is the Arctic ice melting. The Arctic is now the fastest warming area in the world, and this has reduced the difference in temperatures between the Arctic and the Tropics. The temperature difference between the Arctic and the tropics directs the jet stream, which has a significant impact on the UK weather. A low temperature difference means a weakened and slow moving jet stream, extending the period of cool, unsettled weather in the UK. It also causes intense heat waves in the summer.
With global warming showing no signs of abating, the extreme swings of the last few years, manifesting itself in instances, such as, the flash floods at the Calder valley and the intense heat waves, last year, could well become the norm.
Some weather scientists attribute the altered and weakened jet stream to weak solar activity, rather than global warming, or the melting of the arctic ice caps. They look back in history to the early 1800s, when a similar weak solar activity had caused extreme weather, similar to what is experienced now. However, no one knows for sure how exactly solar activity takes place, and there is much speculation involved.
Both the solar activity and the melting ice caps may well be working in tandem to deliver the crazy weather we are experiencing now.