A Note: Global Warming Threads

[iceaura]

What the paper does suggest though is that the risk from methane is much more likely to be a chronic issue (adding to the global burden of GHGs) then it is a disaster scenario because:

The paper glosses over the feedback issue, and says little about how high the new plateau of "chronic" would be or how fast a rise we are at risk for, to get there.

And as pointed out by several people here, a sufficiently rapid feedback boost to a sufficiently high level of "chronic" release (I see you've upgraded from "background") would qualify as a disaster under almost anyone's criteria.

 

[adoucette]

The article does say something about 10% of something.

SO WHAT?
It doesn't say 10% to 13% would be affected by rising seas and that's what you claimed it said.

Why is it you can't friggin admit when you are wrong?

I don't know why you said anything about 1/10% of 7 billion, but you did.

I clearly explained what that reference was to in post 753.

Arthur

 

[Trippy]

The paper glosses over the feedback issue, and says little about how high the new plateau of "chronic" would be or how fast a rise we are at risk for, to get there.

Take a closer look at Figure 2 in Archer 2007.

Or better yet, take a look at the original, bigger version, Figure 12, in Archer 2005.

 

[iceaura]

The paper glosses over the feedback issue, and says little about how high the new plateau of "chronic" would be or how fast a rise we are at risk for, to get there.
”
Take a closer look at Figure 2 in Archer 2007.

Or better yet, take a look at the original, bigger version, Figure 12, in Archer 2005.

Sure. Did that last week. So?

 

[Trippy]

Sure. Did that last week. So?

So it deals with the levels of methane in the atmosphere, and the radiative forcing for the various methane release scenarios.

So for example a release of 5000 Gigatons over a period of 1000 years would result in a peak concentration of Atmospheroc methane of 6ppm decaying rapdily back to background levels in about 10,000 years, and a radiative forcing of the methane of around 1 w/m[sup]2[/sup], a peak CO[sub]2[/sub] of 1800ppm, decaying to around 600ppm after around 40,000 years - taking Clathrate destabilization into account (I think) - the dotted lines are the 'no clathrate' runs.

Which would seem to render:
"...says little about how high the new plateau of "chronic" would be or how fast a rise we are at risk for, to get there..."
Moot, because this is precisely what Fig 2 deals with - how quickly, and how much.

The solid line takes into account additional clathrate releases due to clathrate instability, the dotted line ignores it.

 

[arfa brane]

The article DID NOT say that 10% would be affected by rising water. YOU MADE THAT BS UP.

It doesn't say 10% to 13% would be affected by rising seas and that's what you claimed it said.

Stop being evasive, the article says what it says: "... globally 10% of the world's population and 13% of the urban dwellers are located within coastal areas below 10 meters elevation."

This is the author's estimate of how many people will be affected globally--10% of the world's population. It says they live within coastal areas below 10 meters elevation, what do you think it means? I suppose you can claim, after all, that I made up the part about that many people being affected by rising water; this is really ony true IF sealevels RISE by a certain amount, and this results in inundation of much of the land below 10 metres elevation ASL.

I'm prepared, by the way, to go the distance and keep demonstrating that your objections are plainly ridiculous.

 

[adoucette]

Stop being evasive, the article says what it says: "... globally 10% of the world's population and 13% of the urban dwellers are located within coastal areas below 10 meters elevation."

This is the author's estimate of how many people will be affected globally--10% of the world's population. It says they live within coastal areas below 10 meters elevation, what do you think it means?

It's a statistic.
It means what it says, what percent of people live within 10 meters of sea level.
That's all that statistic means and nowhere in the article does the author say that all these people will be affected by sea level rise (indeed, since the article is only on the EU coastal states, one would not expect the author to make a blanket statement about all the global coastal dwellers).

I suppose you can claim, after all, that I made up the part about that many people being affected by rising water;

You did make that up, it is NOT in the text. It's not even implied by the text.

this is really ony true IF sealevels RISE by a certain amount, and this results in inundation of much of the land below 10 metres elevation ASL.

Yes, and there is no scientific study that I'm aware of that presumes that much of the land below 10 meters elevation will be inundated this century.

This text though does presume the IPCC estimate is low and projects a much higher .50 to 1 meter rise this century, but even that would clearly leave MOST of the area that 10% live on unaffected even if nothing were done.

But the OPPOSITE of what you are claiming is actually the author's conclusion (at least for the EU):

Considerable amounts of damage can be avoided by relative low investments on coastal adaption for most EU coastal member states.

(bolding mine)

So the text points out, that the people in the area he was studying mostly won't be affected, even if sea levels rise ~twice that of the IPCC projections by making some relatively low cost investment in coastal adaption. This is the factor you keep leaving out and I keep having to point out to you (and which the IPCC did a great deal of work on) and that is that we will prevent much of the impact by these adaptave methods. The text also points out that the cost of doing so varies quite a bit, so while on average the cost is low, that doesn't mean it will be low for everybody.

And to be clear, the IPCC refers to a two pronged strategy, Mitigation and Adaption to deal with climate change.
Mitigation is the reduction of GHGs in the atmosphere, primarily through (but not limited to) reduction of per capita emissions and land use changes.
Adaption is the infrastructure changes we can make to reduce the negative impacts of climate change.

Arthur

 

[adoucette]

Bad news again for NASA and it's Earth Monitoring program.

NASA's Glory atmospheric research mission satellite crashed into the southern Pacific Ocean Friday after a protective nose cone fairing failed to separate during launch aboard an Orbital Sciences Corp. Taurus XL rocket. The $424 million failure was the second in a row for Orbital Sciences following the 2009 loss of another environmental satellite because of a similar nose cone malfunction.

This was the second failure in a row for a Taurus XL rocket. NASA's $273 million Orbiting Carbon Observatory was lost during launch Feb. 24, 2009, when it suffered a similar nose cone fairing failure. Orbital Sciences redesigned the system in the wake of that failure, replacing a hot-gas pressurization system with more robust pressurized nitrogen system borrowed from the company's Minotaur rockets.

The 1,200-pound solar-powered Glory spacecraft, also built by Orbital Sciences, was designed to precisely measure how much solar energy enters and leaves Earth's atmosphere and how small particles called aerosols, both man made and natural, affect the global environment.

The satellite's Total Irradiance Monitor, built by the University of Colorado's Laboratory for Atmospheric and Space Physics, was designed to monitor the sun during the daylight portion of each orbit to provide six-hour and daily averages of the total solar energy coming into Earth's atmosphere.

The Aerosol Polarimetry Sensor, built by Raytheon Inc., was designed to measure "the size, quantity, refractive index and shape of aerosols," according to the mission website. "This is the first space-based instrument to be able to identify different aerosol types, which will help researchers distinguish the relative influence of natural and human-caused aerosols in our global climate."

By WILLIAM HARWOOD
CBS News

 

[arfa brane]

So the text points out, that the people in the area he was studying mostly won't be affected, even if sea levels rise ~twice that of the IPCC projections by making some relatively low cost investment in coastal adaption.

Are you saying the cost of these relatively low cost investments won't have any effect on the people who make them, or, these investors will make money?

The text also points out that the cost of doing so varies quite a bit, so while on average the cost is low, that doesn't mean it will be low for everybody.

So you're saying it will affect people in different parts of the world, but "differently"?

 

[arfa brane]

Yes, and there is no scientific study that I'm aware of that presumes that much of the land below 10 meters elevation will be inundated this century.

From UNEP's site:

Population, area and economy affected by a 1 m sea level rise (global and regional estimates, based on today's situation)

Population, area and economy affected by a 1 m sea level rise (global and regional estimates, based on today's situation). Even for today’s socio-economic conditions, both regionally and globally, large numbers of people and significant economic activity are exposed to sea-level rise. The densely populated megadeltas are especially vulnerable to sea-level rise. More than 1 million people living in the Ganges- Brahmaputra, Mekong and Nile deltas will be directly affected simply if current rates of sea-level rise continue to 2050 and there is no adaptation. More than 50 000 people are likely to be directly impacted in each of a further nine deltas, and more than 5000 in each of a further 12 deltas. Some 75 per cent of the population affected live on the Asian megadeltas and deltas, with a large proportion of the remainder living on deltas in Africa. These impacts would increase dramatically with accelerated sea-level rise. The economy part of this graphic represents the annual share of economy in this zone, in GDP (market exchange rates).

--http://www.google.co.nz/url?sa=t&so...__W9AQ&usg=AFQjCNH-uDFLMQXbh1S01o_U0pBUK5qrbQ

ed: I've bolded parts of the subtext for the diagram to aid those with an unsatisfactory reading comprehension situation.

 

[Trippy]

Yes, and there is no scientific study that I'm aware of that presumes that much of the land below 10 meters elevation will be inundated this century.

Population, area and economy affected by a 1 m sea level rise (global and regional estimates, based on today's situation)

1m ≠ 10m

 

[arfa brane]

7 million ≠ 10% of ~7 billion.

Since 10% ≠ 0.1%.

 

[Trippy]

7 million ≠ 10% of ~7 billion.

Since 10% ≠ 0.1%.

The EU ≠ The World.

 

[iceaura]

So it deals with the levels of methane in the atmosphere, and the radiative forcing for the various methane release scenarios.

According to its assumptions, which include rapid oxidation of the methane (no saturation of the buffer) and universally slow temperature response of the Arctic deeper water, and water vapor ignored, and ice cover ignored, and large changes in current patterns ignored, and so forth.

All of this projected over a thousand years, with no probability calculations of possible feedback loops visible or considered.

It's a picture of the effect of the CO2 warming on the methane release, both direct and indirect from oxidized methane, assuming nothing else is going to change very much - all responses to increasing methane are going to be as observed now, ongoing - for the next thousand years.

 

[Trippy]

According to its assumptions, which include rapid oxidation of the methane (no saturation of the buffer) and universally slow temperature response of the Arctic deeper water, and water vapor ignored, and ice cover ignored, and large changes in current patterns ignored, and so forth.

All of this projected over a thousand years, with no probability calculations of possible feedback loops visible or considered.

It's a picture of the effect of the CO2 warming on the methane release, both direct and indirect from oxidized methane, assuming nothing else is going to change very much - all responses to increasing methane are going to be as observed now, ongoing - for the next thousand years.

The primary production of Hydroxyl radicals is through a reaction between Ozone and water, Methane is not involved in this, nor does it mediate this. I mention this because it's important to note that Methane levels have no influence on the rate at which hydroxyl radicals are produced, only the rate at which they are consumed.

According to SAP3-4 Chapter 5 (which I've linked to previously) an abrupt release of 1Tg of Methane will cause a lengthening of the half life of methane by 41%.

Archer comes to the conclusion, based on his models, which successfully reprpoduce field observations, that if the melting timescale (of Clathrates) is shorter than 1000 years is likely, then we would be unlikely to have the significant clathrate deposits we observe today.

SAP3-4 also gives gives a Methane half life of 9 years (well, 8.9 anyway).
1000 years represents 111 half lives.
Even if a release of 5000 GT in a period of 1000 years were to increase halflife of Methane by an order of magnitude to 90 years (a 1000% increase) then a period of 1000 years would still represent 11 Halflives, which would be sufficient to reduce the methane level by 99.5%

Ultimately though, there is a non-zero minimum rate at which Methane can be oxidized which will be approached asymptoticaly as the levels of atmospheric methane increase.

Slow warming of the water column is a prediction of his models, not an assumption.

 

[Trippy]

Addendum to the above:

Allow me to quote from Archer 2005:

The mechanisms by which the clathrate reservoir might decrease in size are more varied, and more difficult to constrain. Pockmarks and landslide deposits on the seafloor document occasional catastrophic releases [Hovland and Judd, 1988; Maslin et al., 1998, 2004], which may be triggered by earthquakes, sediment loading, or isostatic rebound. The catastrophic interaction with temperature scenario would be for clathrate to melt at the base of the stability zone, generating bubbles of methane [Kayen and Lee, 1991]. The increase in volume accompanying this transition increases the hydrostatic pressure of the sediment column, destabilizing the sediment pile to landslides. Eventually, the excess hydrostatic pressure spike diffuses away, so this mechanism might be more responsive to faster temperature perturbations. The methane release from a single landslide would be fast, but the decomposition of the entire clathrate reservoir would probably be accomplished by a series of landslides, rather than a single catastrophic event. Clathrate deposits in the Arctic Ocean may respond first to global warming, because they are found at shallow depths in the cold water column, and because warming is most intense in high latitudes. Our model will not resolve special cases like these in this paper. The minimum response time of the global clathrate reservoir overall to thermal forcing is determined by sediment column warming timescale, several thousand years.

So your objections have been explicitly addressed, speculated upon, and set to one side as being outside the scope of the paper.

So you're objecting to something not being in the paper, that the paper explicitly stated would not be in the paper..?

 

[arfa brane]

From the UNEP site again:

Using the IS92 emission scenarios, projected global mean sea level increases relative to 1990 were calculated up to 2100. Taking into account the ranges in the estimate of climate sensitivity and ice melt parameters, and the full set of IS92 emission scenarios, the models project an increase in global mean sea level of between 13 and 94 cm.

Note that 94cm ≠ 0.6 metres.

 

[Trippy]

From the UNEP site again:

Using the IS92 emission scenarios, projected global mean sea level increases relative to 1990 were calculated up to 2100. Taking into account the ranges in the estimate of climate sensitivity and ice melt parameters, and the full set of IS92 emission scenarios, the models project an increase in global mean sea level of between 13 and 94 cm.

Note that 94cm ≠ 0.6 metres.

So?

From UNEP's site:
...rates of sea-level rise continue to 2050 and there is no adaptation

2050 ≠ 2100

This text though does presume the IPCC estimate is low and projects a much higher .50 to 1 meter rise this century, but even that would clearly leave MOST of the area that 10% live on unaffected even if nothing were done.

0.5<0.94<1

 

[arfa brane]

Just to round out the discussion, the EU isn't the world, and estimates of mean sealevel rise for EU countries aren't a global estimate, the paper adoucette linked to has estimates for both.

And I have never claimed that everyone living below 10 metres ASL will be inundated. I repeated what the authors said: that many people could be affected over the next century. This is because, unlike adoucette, they take into account the possibility that there could be a rise of several metres, not one or less than one.

I wonder why they're doing this? Is there like, some kind of uncertainty in the predictions, or something?

Oh, wait. Yeah, there is. Enough that a rise of several metres can't be discounted from this end of the upcoming century.
But several metres is still less than 10 metres, you say? Yes, but because of tides and storms, that becomes less meaningful as some kind of "boundary" for the global effect of rising seas.

 

[Trippy]

Just to round out the discussion, the EU isn't the world, and estimates of mean sealevel rise for EU countries aren't a global estimate, the paper adoucette linked to has estimates for both.

And I have never claimed that everyone living below 10 metres ASL will be inundated. I repeated what the authors said: that many people could be affected over the next century. This is because, unlike adoucette, they take into account the possibility that there could be a rise of several metres, not one or less than one.

I wonder why they're doing this? Is there like, some kind of uncertainty in the predictions, or something?

Oh, wait. Yeah, there is. Enough that a rise of several metres can't be discounted from this end of the upcoming century.
But several metres is still less than 10 metres, you say? Yes, but because of tides and storms, that becomes less meaningful as some kind of "boundary" for the global effect of rising seas.

No they don't.

Have you even looked at McGranahan 2007? (it's where the 10% in Arthurs link comes from).

I quote directly from McGranahan 2007, the source of the 10% figure used in Costa, Tekken and Kropp.

Sea-level rise is not expected to reach anything like 10 metres above the current mid-tide elevations, at least in the foreseeable future. Even with storm surges, the 10 metres elevation leaves a large margin of safety regarding direct flooding. Sea-level rise and storm surges can certainly cause damage to people living well above the high-water level, through saline intrusion into the groundwater, for example. However, the principal reason for choosing this elevation is that estimates based on elevations below 10 metres could not be considered globally reliable, particularly in some types of coastal areas such as those characterized by mountainous bays.

So the 10m used for the LCEZ isn't a reflection of the fact that the expect the sea level to rise by that much. And when they say affected, they don't neccessarily mean directly by sea level rise, they also include indirectly by things such as the increased frequency of storm surges, saline ground water intrusion and so on and so forth.

Even Ramstorf (2007) only predicts a (maximum) sealevel rise of 1.5m by 2100.