Friday, January 20, 2006

Sea level rises revisited

news @ nature.com�-Sea-level rise is quickening pace - Data crunch confirms model predictions of flooding coastlines.

In the interests of fairness to the "Tuvalu is sinking" crowd, readers are referred to the above article which indicates that maybe sea level rises are faster than I claimed in my previous post. However, I still don't see reason to panic.

As I noted before, Labor and the Greens are claiming that South Pacific islands are at risk of needing to evacuated due to sea level rises in the next decade. I noted that evidence from 2000 suggested a total rise in the next decade of maybe 8 mm. Even allowing for faster rises, I suggested allowing 12 mm as a rough "generous" estimate. (I am embarrassed to note that I called that "half a centimeter", rather than half an inch. I have revised the post now!)

Anyway, the News@nature story above points out that new estimates, using satellite data together with tide gauges, indicate that the current rate is maybe 3 mm per year. However, they also point out that the rate has gone up and down over the last century, and there would seem to be no clear understanding why it varies so much.

So, if we allow 3mm per year as the current rate, that would mean 30mm in a decade. Let's try to get it right this time - that would be 3 cm, or a bit over an inch.

(But also remember from my last post that the sea level sometimes actually drops dramatically around some islands too.)

I still therefore suspect that no one can realistically say that an increase in sea level in the order of 1 inch is going to mean Tuvalu needs to be evacuated.

2 comments:

Anonymous said...

If you haven't actually been on that dot tv island then do the world a favor and STFU !!!


:)

Anonymous said...

to anonymous: so only people who have visited Tuvalu are qualified to talk about whether it's sinking?