Sunspot activity, which follows an 11-year cycle, is due to peak in 2013 after which it will start to wane slightly. But astronomers think the next upswing will be less intensive than normal, or could fail to happen at all. That could affect weather on Earth because low solar activity has been linked to low global temperatures in the past.

Three studies, presented at a meeting of the American Astronomical Society’s solar physics division, all point towards declining sunspot activity into the next decade.

Between 1645 and 1715 almost no sunspots were observed, a solar period which came to be called the Maunder Minimum. During those decades Europe suffered frequent unusually harsh winters, and the time was later termed the Little Ice Age.

But Joanna Haigh professor of atmospheric physics at Imperial College London, cautioned: “In any case, the cooling effect is only ever temporary. When the sun’s activity returns to normal, the greenhouse gases won’t have gone away.”

A secret £7 million weather project in Abu Dhabi has resulted in dozens of man-made rainstorms, according to reports.

Scientists employed by Sheikh Khalifa bin Zayed Al Nahyan, president of the UAE and leader of Abu Dhabi, successfully created more than 50 rainstorms in the state’s Al Ain region last year, mostly in July and August when there is virtually no rain at all. It is believed to be the first time the system has produced rain from clear skies.

They have been using giant ionizers, shaped like giant lampshades, to generate fields of negatively charged particles, which create cloud formation.

In a company video, seen by The Sunday Times, Helmut Fluhrer, the founder of Metro Systems International, the Swiss company in charge of the project, said: “We are currently operating our innovative rainfall enhancement technology, Weathertec, in the region of Al Ain in Abu Dhabid. We started in June 2010 and have achieved a number of rainfalls.”

From the Examiner:

A curious thing has happened over the 2009 - 2010 winter season – Arctic sea ice has rebounded to near normal levels. Long pointed to as a sign of the impact of global warming, the extent of sea ice had been shrinking in recent years.

According to the National Snow and Ice Data Center (NSIDC), the maximum extent for Arctic sea ice was reached on March 31st. This is the latest date maximum extent has been reached since 1979 when satellites began measuring the Arctic Ice.

Read more at the Examiner]

Recently both Russia and China have claimed to be able to use cloud seeding to increase rainfall and snowfall, or change the location of where it falls. In the past, snow-making experiments have been carried out in North American ski resorts in the past with little evidence of success. So how have the Russian and Chinese scientists achieved this feat and what evidence is there that it is in fact due to cloud seeding?

The seeding method used is to add tiny particles of silver iodide to the clouds and there is solid science behind this method. At temperatures a few degrees below zero degrees centigrade, clouds consist mainly of supercooled water droplets. These clouds can be quite stable, but silver iodide has an ice-like structure and it will cause a few of these water droplets to freeze. Once you have ice particles mixed in with the supercooled droplets, these crystals grow rapidly to form snowflakes, causing the cloud to precipitate. The effect is that the water is released from the cloud.

[Read more at The Independent]