Sea levels set to rise by up to a metre: report

[Teh One Who Knocks]

by Madeleine Coorey


SYDNEY (AFP) – Sea levels are set to rise by up to a metre within a century due to global warming, a new Australian report said Monday as it warned this could make "once-a-century" coastal flooding much more common.

The government's first Climate Commission report said the evidence that the Earth's surface was warming rapidly was beyond doubt.

Drawn from the most up-to-date climate science from around the world, the report said greenhouse gas emissions created by human industry was the likely culprit behind rising temperatures, warming oceans, and rising sea levels.

Its author Will Steffen said while the report had been reviewed by climate scientists from Australian science body the CSIRO, the Bureau of Meteorology and academics, some judgments, including on sea levels, were his own.

"I expect the magnitude of global average sea-level rise in 2100 compared to 1990 to be in the range of 0.5 to 1.0 metre," Steffen said in his preface to "The Critical Decade".

He said while this assessment was higher than that of the Intergovernmental Panel for Climate Change in 2007, which was under 0.8m, it was not inconsistent with the UN body which had said higher values were possible.

"We're five years down the track now, we know more about how those big ice sheets are behaving," Steffen told reporters.

"In part we have some very good information about the Greenland icesheet. We know it's losing mass and we know it's losing mass at an increasing rate.

"So that's telling us that we need to extend that upper range a bit towards a metre. Now there are commentators who say it should be even higher than that."

The report said a sea-level rise of 0.5m would lead to surprisingly large impacts, with the risk of extreme events such as inundations in coastal areas around Australia's largest cities of Sydney and Melbourne hugely increased.

Steffen said in some instances, a one-in-a-hundred year event could happen every year.

"The critical point is we have to get emissions turned from the upward trajectory to the downward trajectory by the end of this decade at the very latest," he said.

"We have to make investment decisions this decade to put us on that long-term trajectory that minimises the cost to our economy."

The report found that Australia, prone to bushfires, drought and cyclones, had also likely felt the impact of rising temperatures in recent years.

In the last five decades the number of record hot days in Australia had more than doubled, increasing the risk of heatwaves and bush fire weather, it said.

Chair of the Climate Commission Tim Flannery said the evidence was becoming more convincing year by year that humans were changing the climate.

"In Australia we are seeing the impacts more clearly, we've seen the sea level rise that was predicted, we've seen the decline in rainfall continue particularly in the southwest of Western Australia, we've seen impacts on the Great Barrier Reef and so forth," he told reporters.

"This is the decade we have to act."

Prime Minister Julia Gillard, who is struggling in the polls as she seeks to introduce a carbon tax to place a price on industry's production of greenhouse gas emissions, seized on the report.

"We don't have time for false claims in this debate. The science is in, climate change is real," she said.

[deebakes]

what's a metre? :-k

[Loser]

I cba to find a chicken little pic this late at night, sorry :lol:

[Deepsepia]

Prime Minister Julia Gillard, who is struggling in the polls as she seeks to introduce a carbon tax to place a price on industry's production of greenhouse gas emissions, seized on the report.

"We don't have time for false claims in this debate. The science is in, climate change is real," she said.

Interesting dilemma for Australia-- lotta coal, but also bone dry and already plenty hot.

I look to the Aussies to see how the climate change political debate goes-- they have so much on the line.

[FBD]

*rips Gilliard mask off of the bastid and bitch slaps al gore*

[Hal-9000]

So most folks here don't think we're affecting the climate?
I'm serious...you don't think that we've affected the overall temperature of the atmosphere through emissions and removing trees? And my favorite, the urban island heat effect?

I don't want to get into a link war where 'my data is better than your data'....I just want to know your feelings on the subject and why please :)


I say that of course we've affected the temperature.I wasn't around 1 million years ago, but I can surmise that pastr forms of organic life on Earth have never changed chemical compositions, created new chemicals and then spewed millions of cubic waste gallons per day both into the air and into water supplies like we have.

Can the melting of glaciers raise the sea level just enough... to cause havoc in some areas of the wold? I think it can.

[DemonGeminiX]

:-k

One meter?

:hand:

Sorry, that's not enough to justify me buying a boat.

[deebakes]

So most folks here don't think we're affecting the climate?
I'm serious...you don't think that we've affected the overall temperature of the atmosphere through emissions and removing trees? And my favorite, the urban island heat effect?

I don't want to get into a link war where 'my data is better than your data'....I just want to know your feelings on the subject and why please :)


I say that of course we've affected the temperature.I wasn't around 1 million years ago, but I can surmise that pastr forms of organic life on Earth have never changed chemical compositions, created new chemicals and then spewed millions of cubic waste gallons per day both into the air and into water supplies like we have.

Can the melting of glaciers raise the sea level just enough... to cause havoc in some areas of the wold? I think it can.

we didn't do anything. it's all cyclical and has been foretold by that preacher dude...

[Arkady Renko]

So most folks here don't think we're affecting the climate?
I'm serious...you don't think that we've affected the overall temperature of the atmosphere through emissions and removing trees? And my favorite, the urban island heat effect?

I don't want to get into a link war where 'my data is better than your data'....I just want to know your feelings on the subject and why please :)


I say that of course we've affected the temperature.I wasn't around 1 million years ago, but I can surmise that pastr forms of organic life on Earth have never changed chemical compositions, created new chemicals and then spewed millions of cubic waste gallons per day both into the air and into water supplies like we have.

Can the melting of glaciers raise the sea level just enough... to cause havoc in some areas of the wold? I think it can.

I pretty much agree with that, it seems clear to me that climate has alredy begun to change, and I'm also convinced that human activities are in no small part responsible for it. But I am not so sure we've already figured out the mechanics of the entire thing so all we can do is try to slow it down and at the same time prepare for the worst. sticking heads into the sand won't do anyone any good.

[Deepsepia]

I pretty much agree with that, it seems clear to me that climate has alredy begun to change, and I'm also convinced that human activities are in no small part responsible for it. But I am not so sure we've already figured out the mechanics of the entire thing so all we can do is try to slow it down and at the same time prepare for the worst. sticking heads into the sand won't do anyone any good.

There are really two parts to the climate predictions: part one is the heating effect of CO2, which is a very simple calculation. CO2 has known absorption spectra, and we're putting a known amount of it into the atmosphere each year. None of that is speculative.

At the level of "what does that mean for sea levels a century from now", much is speculative. Its a system with so many feedbacks that we're very unlikely to get it right. The denialists seize on appropriate skepticism about the specifics of out year models to cast doubt on the entire proposition-- which is wrong.

I always come back to "we're doing an atmospheric chemistry experiment with the only atmosphere we have-- do you think that's a good idea?" The answer is, obviously, no. Many things can go wrong. Some we've thought of and are worried about (warming, acidification of oceans) -- but its equally likely that something devastating will occur that we haven't thought of.

Think of agriculture-- the 7 billion people on the planet are fed by a very small number of crops, and CO2 is a critical input into all plant systems. Now higher CO2 is observed to make some things grow faster-- but it also makes weeds grow faster.

Before this century is out, some environmental catastrophe will result in a billion deaths . . . that's my bet.

[Arkady Renko]

I hear you on the carbon dioxide, but I still wonder how heavily other influences such as methane weigh in. My concern is that we might waste trillions on reducing CO2 emissions while they're only one factor among several. I'm not sure if that money and effort might be better directed at containing the damage climate change will cause.

[Deepsepia]

I hear you on the carbon dioxide, but I still wonder how heavily other influences such as methane weigh in. My concern is that we might waste trillions on reducing CO2 emissions while they're only one factor among several. I'm not sure if that money and effort might be better directed at containing the damage climate change will cause.

Methane weighs very heavily, as does water vapor. My worries aren't "CO2 or methane" -- its all of them.

The methane component is particularly of concern as a feedback that accelerates climate change. The argument goes: "Massive amounts of methane are held in frozen permafrost and in the sediments of arctic lakes-- warm the arctic by a few degrees, and this stuff comes out of its freeze, into the atmosphere"

As methane trap significantly more heat than CO2, you get a process where the heating may end up being much greater than is presently predicted from CO2 based models . . . not something where we can speak with certainty.

What we can say is that its very, very risky.

[FBD]

Co2 is not going to cause anything aside from helping plants grow a little better. What everyone keeps missing is that the warming coefficient for CO2 is not linear, it is logarithmic, and we're sufficiently high up the spectral absorption curve that the difference between 380, 450, 550ppm is negligible at best.

It will not be lethal to humans until roughly 25,000ppm, which is far more than we've ever had or ever will have in our atmosphere here.

Ya damn straight our money will be better spent elsewhere. A trillion for a possible degree prevented? :roll:


Were I to side with deep on that bet, I'd be betting the deaths would be from cold, not heat. Cold kills a LOT more mofos than heat, and we can plainly see the effects of even a small sun-funk from this past year & change.

We need to concentrate efforts on keeping things clean, not trying to find a scapegoat to justify massive new taxes, which is basically all this cap and trade garbage is.


Climate's changing, it always will - and humans are a small part of that change. To think that we're even close to a primary driver of the climate is quite presumptuous, UHIs and such even.

The earth is not some closed system like all these models keep treating it. We lose a shitload of heat to space, there's tons of negative feedbacks...

f'n waste of time even discussing CO2, honestly.

[Teh One Who Knocks]

I don't want to get into a link war where 'my data is better than your data'....I just want to know your feelings on the subject and why please :)

Nope, I don't buy into it. Do we as humans have an effect on the global temperature? Sure, but it's minute compared to what people pushing Global Warm...sorry, Climate Change would have you believe.

You do realize that there are times in out planet's history where CO2 levels were MUCH higher than they are now? Everything is cyclical.

:2cents:

[Teh One Who Knocks]

One chart tho :)


Global Temperature and Atmospheric CO2 over Geologic Time

http://i.imgur.com/4gmU4.gif

Late Carboniferous to Early Permian time (315 mya -- 270 mya) is the only time period in the last 600 million years when both atmospheric CO2 and temperatures were as low as they are today (Quaternary Period ).

[Hal-9000]

Very interesting, I see...
I was under the impression humans had only measured and quantified actual atmospheric trends over the past 300 years....as there were no instruments or data gathering thousands of years ago.


So how can we say - This is just a little blip the Earth goes through, when we haven't been able to record other blips and trends?


I only know what I can see and experience for myself.In my lifetime, the weather has changed dramatically. I also know that any age of previous man, never had the level of industrialization we have experienced in the past 100 years.

Maybe a chart showing the world's CO2 levels from 1800-1900 vs 1900-2000? Or did we have accurate ways of measuring the data in the 1800's?