neal
We know that we are on the long end of coming out of an ice age
You have a citation for this?
Climate changes due to forcing events .... Our ice ages were caused by forcing events...
A common skeptic argument is that climate has changed naturally in the past, long before SUVs and coal-fired power plants, so therefore humans cannot be causing global warming now. Interestingly, the peer-reviewed research into past climate change comes to the opposite conclusion. To understand this, first you have to ask why climate has changed in the past. It doesn't happen by magic. Climate changes when it’s forced to change. When our planet suffers an energy imbalance and gains or loses heat, global temperature changes.
There are a number of different forces which can influence the Earth’s climate. When the sun gets brighter, the planet receives more energy and warms. When volcanoes erupt, they emit particles into the atmosphere which reflect sunlight, and the planet cools. When there are more greenhouse gases in the atmosphere, the planet warms. These effects are referred to as external forcings because by changing the planet's energy balance, they force climate to change.
It is obviously true that past climate change was caused by natural forcings. However, to argue that this means we can’t cause climate change is like arguing that humans can’t start bushfires because in the past they’ve happened naturally. Greenhouse gas increases have caused climate change many times in Earth’s history, and we are now adding greenhouse gases to the atmosphere at a increasingly rapid rate.
Looking at the past gives us insight into how our climate responds to external forcings. Using ice cores, for instance, we can work out the degree of past temperature change, the level of solar activity, and the amount of greenhouse gases and volcanic dust in the atmosphere. From this, we can determine how temperature has changed due to past energy imbalances. What we have found, looking at many different periods and timescales in Earth's history, is that when the Earth gains heat, positive feedbacks amplify the warming. This is why we've experienced such dramatic changes in temperature in the past. Our climate is highly sensitive to changes in heat. We can even quantify this: when you include positive feedbacks, a doubling of CO2 causes a warming of around 3°C.
What does that mean for today? Rising greenhouse gas levels are an external forcing, which has caused climate changes many times in Earth's history. They're causing an energy imbalance and the planet is building up heat. From Earth's history, we know that positive feedbacks will amplify the greenhouse warming. So past climate change doesn't tell us that humans can't influence climate; on the contrary, it tells us that climate is highly sensitive to the greenhouse warming we're now causing
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http://www.skepticalscience.com/climate ... period.htmI suspect that there are significant changes ocurring today that will impact energy use, and therefore CO2 emissions. For instance LED technology will probably replace flourescent technology for light bulbs over the next 10 to 15 years. The savings in electrical power use that this will generate will be enormous. I don't think there is any particular magic bullet, nor does it make sense for government to manage all the change. Today, the market is largely driving a lot of this change. (Building owners seekling ways to reduce electrical use and save money on power and maintenance. Electric cars gaining a foothold in the market as gas prices rise.... .)
However, we are already witnessing significant effects from a warming climate. The idea that we know how to mitigate all the effects, or even could is probably folly. But the first step to being able to adapt to the change is admitting thats it happening. In the high arctic its already happening as far north communities look at things like moving to "air ships" (we used to call them dirigibles but now they have a great deal more structural integrity) for communication as ice roads become undependable and shipping remains seasonal.. Corporations and business is moving ahead of governments on this, which is a good thing since some governments are incapable of acting effectively.
The biggest worry is how to deal with rising oceans. Shore front Erosion will be and already is increasing as a problem in many parts of the globe.
http://www.thestar.com/news/world/artic ... ays-reportIt was interesting to read the backlash on Michelle Bachmans campaign statements about drilling in the Florida Everglades. Apparently a non-starter and she's stepped it back to qualify as "If we can drill responsibly." I agree with her...And I'd apply the same statement to offshore drilling or any other kind of energy scheme.
To me thats always the question. What is "responsible"? Its obvious that Deepwater Horizon wasn't responsible. Given a regulatory environment where they were left to their own judgement on the methods they were employing... they chose the cheaper more risky options.
Unfortunately, without effective third party (government) oversight of "responsible behaviours, private enterprise will often act with more risk then potentially affected stakeholders would prefer. (For Horizon that would be derrick workers, the fisheries and tourism. )
It would be intersting to hear what Bachman thinks can guarantee "responsible drilling"...in the everglades or anywhere.