Musing on sea level rises

A friend of mine is presenting about climate policy this week, and
wanted some visuals about sea level rises under climate change

Current estimates of total sea level rise are for 2 metres in 100 years
- from all sources in both hemispheres. Will Steffen at ANU has gone on
record saying that, although unlikely, a 4 metre rise cannot be ruled
out; Jim Hansen is saying similar things.

Yet it can be hard to get people to realise the severity of a 2 metre
change. Most westerners are pretty OK (apart from some people in
beachfront suburbs) and have the money anyway to build levees, etc.

The web site http://flood.firetree.net/ has a great mapping tool, but an
average 2 meter rise missed the real danger - tidal surges.

Greater expected volatility of weather means we get bigger tidal surges.
When you combine these with a 2 metre rise in sea levels, you get a lot
of coastal flood stories, with the world's big deltas being regularly
covered in salt water. That will lead to food disasters, as some of the
world's great food bowls are deltas (Nile, Red River, Mekong, Yangtze,
Indus, Ganges/Bramaputra) meaning a disproportionate number of people
are exposed to a small change in sea levels. It is true that we may be
able to adapt crops to more saline conditions (a great hope), but lots
of the deltas will be flooded too frequently for even that.

Plus a lot of big cities will get flooded regularly. Even in London one
forecast is that the Thames Barrier will be breached by 2030, flooding
large areas of East London (and thousands of dwellings have been allowed
to be built behind the Barrier on the basis that they are now protected
from flooding risk!). Translate that to calamities in Guangzhou,
Shanghai, Nanjing, Tianjin, Saigon, Kolkotta, Chennai, Mumbai, Lagos,
Miami, New Orleans - 140 million people just there - and we have some
big disaster issues.

The reason the Arctic sea ice story is so important is ....

1. It's a key "canary in the coal mine". The amazing rapidity of change
in summer sea ice extent is an indicator of climactic changes globally.
With the rate of global greenhouse gas emission increases having gone up
sine the 1990s from an average of 1.1% p.a. to an average of 3.1% this
decade (now 3.4% according to a report I saw today) it's perhaps not
surprising that the whole thing is getting away from us.

2. The sea ice disappearance is one of the most significant tipping
points because of the loss of its albedo effect - a large slab of the
earth goes from being a heat reflector to a heat absorber. Not good.
It's also a harbinger of the mother of all tipping points - the thawing
of clathrates under the Arctic sea and the consequent vast release of
methane gas.

Check out these videos from a leading Arctic researcher that show what
methane gas seepage looks like:
http://www.alaska.edu/uaf/cem/ine/walter/videopage.xml. Sort of amusing
really, but methane gas is, of course, 20 times more potent a greenhouse
gas than carbon dioxide. Swedish scientists are already reporting an
increase in the ocean bubbling you see.

That means a lot more 40+ degree weeks in Australian summers, and a lot
more bushfire.

Sean

Three sobering facts about climate change

Courtesy of the Environmental Defense Funds
(http://www.edf.org/page.cfm?tagID=35792)

35%
Increase in the global carbon dioxide emissions from the burning of
fossil fuels since the Kyoto Protocol was signed in 1992.

1000 years
Length of time changes in the earth's surface temperature, rainfall, and
sea level will remain even after carbon dioxide emissions are completely
stopped.

US$427 million
Amount spent by the (US) oil and coal industries in the first six months
of 2008 in political contributions, lobbying expenditures and
advertising to oppose climate action.

A response to UK Met office fears that 'distorted' climate change claims undermine efforts to tackle carbon emissions

'Apocalyptic climate predictions' mislead the public, say experts
Met Office scientists fear distorted climate change claims could
undermine efforts to tackle carbon emissions

See:
http://www.guardian.co.uk/environment/2009/feb/11/climate-change-misleading-claims
----------------------------

I have the highest regard for the Met Office; this article is a useful
reminder to be careful about making predictions based on immediate
events, and a very useful reminder to remain sober in our deliberations.

The danger, of course, to much sobriety has an enervating rather than
directive influence on political decision-makers.

Vicky Pope doesn't deny the possibility of an ice-free Arctic by 2013
(as suggested by a number of researchers - see
http://www.nature.com/climate/2008/0807/full/climate.2008.63.html, and
Jim Hansen's writings).

Her argument is about people suggesting calamity when there is still
much doubt.

However, for those of us trying to weigh up risks, the question is more
how likely is the fast melt scenario and what does it mean. There is no
doubt that there is a consistent decrease in summer ice cover in the
Arctic (The US National Snow and Ice Data Center, for example, reports a
consistent 3.1% p.a. decrease in Arctic ice cover over the last 30 years).

There is also no doubt that there has been a serious increase in the
rate of summer melting in recent years that, if it kept up, would result
in disappearing summer ice cover in a few short years. There also seems
little doubt that if summer ice disappears entirely we lose an important
climate stabilising factor (the ice's albedo effect) and the risks of
more rapid climate change then increase exponentially.

The debate is about the likelihood of that recent increased rate of
melting being a blip or a trend. From a political decision-makers point
of view, there are enough scientists arguing that it's highly likely (if
only because of the range of ancillary climate indicators that alert us
to more rapid climate changes than expected) that we should treat this
as a significant probability.

If we were flying a passenger aeroplane that would be enough risk for us
to take emergency evasive action. That's what we need to do.

Great Age article on the Australia fires and climate change

Fires the deadly inevitability of climate change
Freya Mathews
The Age
February 10, 2009

The disaster challenges the Government to accept evident truths.

IT IS only a couple of years since scientists first told us we could
expect a whole new order of fires in south-eastern Australia, fires of
such ferocity they would simply engulf the towns in their path. And here
they are.

The fires we saw on Saturday were not "once in a thousand years" or even
"once in a hundred years" events, as our political leaders keep
repeating. They were the face of climate change in our part of the world.

These fires are simply the result of the new conditions that climate
change has introduced here: raised temperatures, giving us hotter days
than we have ever experienced before combined with lower rainfall giving
us a drier landscape. Let's stop using the word "drought", with its
implication that dry weather is the exception. The desiccation of the
landscape here is the new reality. It is now our climate.

Rest of article at ....
http://www.theage.com.au/opinion/fires-the-deadly-inevitability-of-climate-change-20090209-8289.html?page=-1

Two useful quotes from Davos 2009

1. Jeremy Oppenheim, global director of climate-change initiatives at
McKinsey: "The transition to a low-carbon economy, if done right, has
the potential to stimulate economic growth, create jobs and bring
benefits to consumers. The 'costs' of this transition are in fact
investments in new, 21st-century infrastructure that will pay off for
generations to come – just as the 'costs' of investments in
electrification, highways, and the internet paid off with very high
returns for the societies that made them in the 20th century."

2. The World Economic Forum's "Green Investing Report" was released at
Davos. It calls for annual global investment of £360 billion in
green-energy infrastructure including wind, solar power, geothermal
energy and biofuels. http://www.weforum.org/en/initiatives/ghg/index.htm

Co-author Michael Liebreich of London-based New Energy Finance:
"Clean-energy opportunities can generate significant economic returns.
The report shows that even after a tumultuous 2008, an index of the
world's 90 leading clean-energy companies had a five-year
compounded-annualised return of almost 10%, unmatched by the world's
main stock indices."

From
http://business.timesonline.co.uk/tol/business/economics/article5627461.ece