And now it's global COOLING! Record return of Arctic ice cap as it grows by 60% in a year

[MANGO]

I think both global warming and global cooling are going on at the same time. Both situations created by man. this is why it is so hard to quantify. Having said that. I also believe that between ice ages, it stands to reason, that at some point, the earth must warm up to a peek high temp before it starts to cool of and become the next ice age. Personally, I am much more concerned with the rising levels of co2 making the air poisonous to breath.

[MadMonk]

Well, this is the basic concept I don't understand.

Global Warming Advocates say mankind has caused Global Warming - yet if there is a small cooling, or slowing down of the "warming" then they say it is insignificant as climate change takes many years.

Well...mankind hasn't been here for "many" years with respect to "climate change".

So which is it? Is climate change long term or short term?

[MadMonk]

I think both global warming and global cooling are going on at the same time. Both situations created by man. this is why it is so hard to quantify. Having said that. I also believe that between ice ages, it stands to reason, that at some point, the earth must warm up to a peek high temp before it starts to cool of and become the next ice age. Personally, I am much more concerned with the rising levels of co2 making the air poisonous to breath.

[silverpig]

Yes I agree that time window matters, and that is exactly what many skeptics fail to understand: "no statistical warming since 1997" is simply the wrong way to look at climate science. I'm not even sure why you brought it up in the first place.

You keep referring to my choice of time period as problematic, but now I'm not sure what you are disagreeing with exactly.

(1) The primary concern is the several degrees of warming over the next century if we continue our current path.

(2) The important point is that even though warming of similar magnitude has been observed over the past 350,000 years, it is fairly certain that the rate of warming is at least 10, if not 100 times faster than those past changes.

What do you disagree with? How will a change in time window change these conclusions?

[silverpig]

Don't worry, Silverpig. You're doing just as well as the rest of us would do against him.

[Heretic]

When one talks about global warming, one typically refers to the energy balance of the earth.

A simple analogy will be a bathtub. If you turn on the tap, then the water level will gradually rise, and as the water level rises, the rate at which it drains will also increase. Eventually you'll get to a point where the rate of filling equals the rate of draining, and you have an equilibrium.

The earth's climates works in an analogous way. The earth's temperature is like the water level in the tub: it is determined via a balance between the energy inflow (the sun), and the outflow (earth continuously release energy into space). Adding greenhouse gas is like clogging the drain: it reduces the outflow, and leads to an increase in temperature.

The earths climate is governed by two knobs: solar input, and greenhouse gas, and the climate changes as soon as these knobs are changed. So the fact that human civilization has only been around for few thousands of years is irrelevant: the day you start dumping CO2 into the atmosphere is the day you start altering the climate.

However, the other part of the question is (a) how long until one can detect the climate change? and ( b ) if I change the knob today, how long before a new equilibrium is estimate, and the climate stops changing?

The two questions are somewhat related, as both has a lot to do with the size of the tub. It takes a while to increase the water level, and thus it also takes longer for a new equilibrium to be established. On the other hand, if you have a small tub, the response to a change in the knobs will be much quicker. For the earth, the ocean is a large tub, as it has a very high heat capacity. As a result full effects of a climate change occurs over 100's of years. (If you include ice sheets, that'll take 1,000-10,000years)

In your quote, "insignificant as climate change takes many years" is actually not the right explanation to why a small cooling or slowing down in atmospheric surface temperature is insignificant (bolded as this is actually an important point).

As I explained, climate change starts the minute you fiddle with the knobs, and thus if you have CO2 in the atmosphere, it causes warming continuously. The issue is, can we detect this signal?

The answer is that if we look at atmospheric temperature alone, it takes a long period of time for the warming to be noticed (a couple of decades or more). As I explained to you in an earlier post: there is constant energy transfer between the atmosphere and the ocean, particularly due to El Nino and La Nina, but if you look at periods of decades and longer, these energy transfers largely cancels out, and it is only then will you be able to detect the global warming signal.

One way to this clearly, is that one can try to estimate and remove the effects of the El Nino and La Nina (plus several other factors) on surface temperature via linear regression, and it is very clear that global warming has not stopped since 1997:

Another important point is that global warming really refers to the accumulation of energy both in the atmosphere and the ocean. And in fact most of the extra energy is going into the ocean, which exhibits very little pause:

[zombieksa]

I don't give a damn about the icecaps! Its 94 degrees and hot as balls in Windsor ON right now.

[MadMonk]

Read my post again.

"Not saying it's not, but you are guilty of choosing your timescales to highlight your point"

I'm not disagreeing with the conclusions, despite your continued efforts to paint me in that light.

[DonLever]

No one has say it yet but here it is:

"The study was paid by the oil companies".

[SabreFan1]

Nope, the Antarctic is still melting .... Global warming is heating up the oceans and the oceans are melting the ice.

http://www.nbcnews.com/science/warm-water-under-antarctic-glacier-spurs-astonishing-rate-melting-8C11140007

[Slegr]

Why is global warming always seen in a negative light? Sure, there might be some negative consequences, but there are likely many positive outcomes, particularly in Canada, where 75% of our inhabitants lives within 161 KM of the US border. Most of Canada is unpopulated because it's too cold / inhabitable. Some global warming may change that, and make our entire country the tourist destination of the world because of it's perfect weather.

[Jimayo]

Why is global warming always seen in a negative light? Sure, there might be some negative consequences, but there are likely many positive outcomes, particularly in Canada, where 75% of our inhabitants lives within 161 KM of the US border. Most of Canada is unpopulated because it's too cold / inhabitable. Some global warming may change that, and make our entire country the tourist destination of the world because of it's perfect weather.

[Slegr]

Well, aside from losing the coastal regions and the deaths that will follow, the climate shift at +3C will mean drought to flood to drought conditions in canada. No temperate rain fall. So growing crops becomes problematic. Massively populated areas of the earth will become uninhabitable.

It's not a desirable end for the human race.

[VICanucksfan5551]

Well, aside from losing the coastal regions and the deaths that will follow, the climate shift at +3C will mean drought to flood to drought conditions in canada. No temperate rain fall. So growing crops becomes problematic. Massively populated areas of the earth will become uninhabitable.

It's not a desirable end for the human race.

[Jimayo]

You sound pretty certain about the potential impacts of global warming on Canada. Climate change has happened since there was a climate, so let's roll with it. Canada has the most to gain from it, and fear mongering is just bothersome. I'm talking about growing bananas in Dease Lake. Going on water slides in Fort Nelson. Populations in the millions. Wha??! Exactly.

[In the Slot]

Nasa is messing with the pictures....govt agency, oil controls the government...easy...

send someone up to check before you beleive it

[Plum]