Global Warming

Global warming could stave off next ice age for 100,000 years

Global warming is likely to disrupt a natural cycle of ice ages and contribute to delaying the onset of the next big freeze until about 100,000 years from now, scientists have suggested.

In the past million years, the world has had about 10 glacial periods before swinging back to warmer conditions like the present.

In the last glacial period known as the Ice Age, which ended 12,000 years ago, ice sheets blanketed what is now Canada, northern Europe and Siberia.

In a new explanation for the long-lasting plunges in global temperatures that cause ice ages, scientists pointed to a combination of long-term shifts in the Earth's orbit around the sun, together with levels of carbon dioxide in the atmosphere.

They said the planet seemed naturally on track to escape an ice age for the next 50,000 years, an unusually long period of warmth, according to the study led by the Potsdam Institute for Climate Impact Research and published in the journal Nature.

But rising man-made greenhouse gas emissions since the Industrial Revolution began in the 18th century could mean the balmy period will last for 100,000 years.

The findings suggest human influences "will make the initiation of the next ice age impossible over a time period comparable to the duration of previous glacial cycles".

Earth's orbit around the sun is oval in shape but this becomes more circular every 100,000 years and more particularly so every 400,000 years.

Global Warming

Prediction of Mini Ice Age for the 2030s Challenged

Climate experts slammed a highly publicised report by a U.K. math professor that suggests Earth will experience a “mini ice age” during the 2030s due to an astounding 60 percent decline in solar activity.

Valentina Zharkova’s study, published last year in the The Astrophysical Journal and highlighted after a recent science conference in Wales, says the magnetic waves that cause sunspots exist in two divergent, and competing frequencies.

Zharkova wrote that the frequencies will cancel each other out within 15 years, leading to a significant reduction in the level of solar radiation that reaches the Earth.

She argues that the quieter sun is on track to cause a drop in global temperatures, similar to a mini ice age from 1645 to 1715 known as the Maunder Minimum.

Climate experts quickly pointed out that the brief cooling was pretty much limited to Europe and to a large extent due to a surge in volcanic eruptions, which caused ash and gas to filter the sun’s rays.

“Any reduction in global mean near-surface temperature due to a future decline in solar activity is likely to be a small fraction of projected anthropogenic (manmade) warming,” scientists wrote in a study published June 23 in the journal Nature.

"The effect is a drop in the bucket, a barely detectable blip, on the overall warming trajectory we can expect over the next several decades from greenhouse warming," Michael Mann, professor of meteorology at Pennsylvania State University, told The Washington Post.

Zharkova is openly skeptical that human activity is the driving force behind the recent warming of the planet.