Check my arithmetic

In the last post, I forecast next year’s September sea ice extent using not only extent data, but latitude of the ice edge. To compute that from extent, I applied a formula given by Eisenman in the supplemental info of his publication.

A reader pointed out that there seemed to be a discrepancy between his numerical values and mine — and he’s right. I’ve double-checked the approximation formula and my program, but I can’t resolve the discrepancy.

Therefore, I’d be grateful if some of you would reproduce the calculation of latitude based on extent data, using Eisenman’s approximation formula. The formula as given is this:

The data I used for sea ice extent is here (it’s monthly averages from NSIDC):

ICE

If you could report the range of latitude values you get from the extent data in that file, using the formula as given by Eisenman, that would confirm or deny that I’ve implemented his formula as stated.

Thanks!

P.S. The figure I used for the radius of the earth is 6371 km.

Sea Ice Forecasts

For several years, I’ve forecast the Arctic sea ice extent to be observed during September (when it reaches its minimum). For the most part my forecasts have been successful, although I was farther off this year than previously because sea ice extent dipped well below the existing trend line — and that’s how I make my predictions, by extending the existing trend line for September sea ice extent, 1 year into the future.

Death by Heat Wave

Since the turn of the millenium, we’ve been struck by some truly notable and very damaging heat waves. Probably foremost in the memory of those who follow such things are the 2003 European heat wave, 2010 in the Moscow region, and just this year in the U.S.

Remember the Alamo

I watched about 8 hours of the 24 Hours of Reality: Dirty Weather Report from Al Gore’s “Climate Reality” project. All in all, I’d say it was excellent. It also made me realize how much more we need to involve the general public, and especially the young adults and near-adults who will bear the brunt of coming climate changes, in our efforts to reverse the lethargy that grips our nation, and to a lesser degree the world, in dealing with the crisis that is global warming.

Climate Reality, again

Just a reminder that the final hour of the Climate Reality broadcast is from 7:00 to 8:00 P.M. Eastern Time tonight. I’ve watched a lot of it already and found it excellent (I’ll have more comments later). I expect the final hour to be especially good.

Climate Reality

Al Gore’s Climate Reality site is kicking off another 24 Hours of Reality broadcast today at 8:00 P.M. Eastern Time. I strongly recommend not only that you watch it, but that you get some friends to watch it with you.

Extreme Denial

Under the guise of a “big picture” look, WUWT reader “just the facts” purports to show that climate data don’t support the claim of an increase in extreme weather. But he (she?) doesn’t show evidence about extreme anything, just a bunch of graphs, which he got from other sources, followed by the wrong conclusions. Show a graph of, say, global average temperature, then say “doesn’t look like there’s been much global warming” (even though there has been), and conclude “no increase in extreme weather here.” And of course “he” goes “out of his way” to use “scare quotes” at “every opportunity.”

What David Suzuki and I have in common

Rather a lot, actually.

Sea Level and la Niña

There’s an interesting graph on the web site of the Univ. of Colorado sea level page comparing de-trended sea level to the multivariate el Niño index:

In The Wake Of Sandy, A 16-Year Old Climate Activist Speaks Her Mind

by Maya Faison

(re-posted from ClimateProgress)

I am 16 years old and I am currently in my home in Laurelton, Queens. It is day six with no heat, no power and no gas in my mom’s car to escape.