Wednesday, June 30, 2010

The heat may be ending

And ending for a long time. A couple of decades, maybe.

I'm no scientist - but I found this interesting. With the unprecedented heat we've had lately, it is easy to believe in global warming. The earth is heating up and human's are at least partially to blame.

But how much? Some researchers say that some of what is happening could be a normal occurrence, or possibly an swing in a natural heating and cooling cycle.

When studying effects of volcano's on climate change, researchers funded by NASA found that.

"The pattern of winter warming following the volcanic eruption is practically identical to a pattern of winter surface temperature change caused by global warming. It shows that volcanic aerosols force fundamental climate mechanisms that play an important role in the global change process."

But they go on to say that human interaction could make the effects of volcanic eruptions on climate worse.

If you look at history, there was a mini ice age as recently as the 1800s. could the current warming trend just be us coming back to normal from then? What were the causes of the mini ice age then?

Wikipedia says:
Several causes have been proposed: cyclical lows in solar radiation, heightened volcanic activity, changes in the flow of ocean currents, an inherent variability in global climate, and a decrease in atmospheric CO2 driven by decreased human populations (e.g. due to the Black Death and the Columbian Exchange).

But even more recently, there is increasing evidence that we may be heading towards more cooling. Apparently, some scientists point to shifts in ocean currents as the culprit in a new trend towards cooler weather.

The bitter winter afflicting much of the Northern Hemisphere is only the start of a global trend towards cooler weather that is likely to last for 20 or 30 years, say some of the world’s most eminent climate scientists.

Their predictions – based on an analysis of natural cycles in water temperatures in the Pacific and Atlantic oceans – challenge some of the global warming orthodoxy’s most deeply cherished beliefs, such as the claim that the North Pole will be free of ice in
summer by 2013.

According to the US National Snow and Ice Data Centre in Colorado, Arctic summer sea ice has increased by 409,000 square miles, or 26 per cent, since 2007 – and even the most committed global warming activists do not dispute this.

The article is a good one and worth reading. The article goes on to quote other scientists with similar views.

William Gray, emeritus Professor of Atmospheric Sciences at Colorado State University, said that while he believed there had been some background rise caused by greenhouse gases, the computer models used by advocates of man-made warming had hugely exaggerated their effect.

According to Prof Gray, these distort the way the atmosphere works. ‘Most of the rise in temperature from the Seventies to the Nineties was natural,’ he said. ‘Very little was down to CO2 – in my view, as little as five to ten per cent.’

I am ignoring a bunch of research on global warming here, I assume we have heard most of these arguments already. What makes things even more interesting is that there are a whole bunch of scientists that believe that global warming may trigger a little ice age.

This article Are We on the brink of a 'New Little Ice Age' discusses just that.

Thinking is centered around slow changes to our climate and how they will affect humans and the habitability of our planet. Yet this thinking is flawed: It ignores the well-established fact that Earth’s climate has changed rapidly in the past and could change rapidly in the future. The issue centers around the paradox that global warming could instigate a new Little Ice Age in the northern hemisphere.

Evidence for abrupt climate change is readily apparent in ice cores taken from Greenland and Antarctica. One sees clear indications of long-term changes discussed above, with CO² and proxy temperature changes associated with the last ice age and its transition into our present interglacial period of warmth. But, in addition, there is a strong chaotic variation of properties with a quasi-period of around 1500 years. We say chaotic because these millennial shifts look like anything but regular oscillations. Rather, they look like rapid, decade-long transitions between cold and warm climates followed by long interludes in one of the two states.

So what to believe? I like to think that since our history is dotted with warmer and cooler periods, cycles make sense. Does human activity most likely exacerbate the changes in our climate and do we need to curb our dependence on fossil fuels? Yeah, probably

For me, a little global cooling would really help my falconry (and that is what it is really all about), and after a hunt the other day with Patrick, I could go for a little cooling.

1 comment:

Diane-Sage said...

With each generation, technology, greed, and gluttony, you bet we are contributing to this global warming.
Yes some has to do with nature taking its "normal" course...but we do not help none eh?