Peugeot trip computer overestimates fuel efficiency.

Two years ago, I suspected that the fuel efficiency that my car’s trip computer calculates was leaner than the actual consumption. Two years and 50,000 kilometers later, this appears to be the case. On average, the trip computer states the car uses 0.75 fewer liters of fuel per 100 km than the actual consumption. That’s about 5 miles per gallon in American units. For whomever cares, the car averages 6.3 liters per 100 km, or 37 mpg, and drags a family of 3.4 people around town and on moderate, occasional road trips.

Figure 1. Actual fuel consumption (blue) vs. stated fuel consumption (pink).

Terminology Question

Is there a less clunky term for "post-Archean"? Obviously, post-Archean has been around since at least the PAAS definition from Nance & Taylor (1976), and it has obvious utility as "the time in Earth's history when the atmosphere contained oxygen", but I was wondering if there is an officially recognized word for it. Anyone?

Is this how circles are supposed to work in Google plus?

Google plus circles can be used to classify people in order of perfidy. Click to enlarge.

Or here is a blow-up if you didn't click the one above.

Warning: Associating geologists who study surface processes with "basement" may cause offence.

2011 Arctic Sea Ice minimum predictions

The 2011 sea ice extent betting pool has now closed. Unlike previous years, we no longer have a distinct multimodal betting population. However, despite my advertising the contest on denialist schill sites, nobody has guessed at a final ice extent anywhere near or above the 1979-200 average (on right). On the other hand, we no longer have large guess populations off-screen to the left, as we have in previous years.

Tune in this October to see who wins.

Peugeot trip computer overestimates fuel efficiency.

Two years ago, I suspected that the fuel efficiency that my car’s trip computer calculates was leaner than the actual consumption. Two years and 50,000 kilometers later, this appears to be the case. On average, the trip computer states the car uses 0.75 fewer liters of fuel per 100 km than the actual consumption. That’s about 5 miles per gallon in American units.


Figure 1. Actual fuel consumption (blue) vs. stated fuel consumption (pink).


Figure 2. overestimation of mileage (mpg).

2011 Arctic sea ice extent minimum prediction pool

Update:
The contest so far:


Neven and Peter are reminded that contestants who have been mathematically eliminated at the 2 sigma level are entitled to guess again. It is up to you guys to keep track, though. This post will remain on top until the contest closes.

original post:

The 2011 Arctic sea ice extent minimum prediction pool is now open. A reminder that this is a competition on extent, not coverage.

The 2010 summed guess curve and final result are shown below:


Guesses are to be in the form of extent and sigma (a mathematical measure of uncertainty), in thousands of km² You may use decimal places if you insist.

Your guess will define a Gaussian curve.

The function with the highest value for x=minimum daily measured ice extent (from IARC-JAXA) wins.

See the 2009 announcement, opening, and final curve for details.

This contest will close much sooner than last year's. Guesses must be submitted by the time the Earth reaches aphelion in its orbit, which the internet tells me is 3 pm on July 4 (UTC). Trash talking, dissembling, and boasting in the comments section is still encouraged.

The prize, as always, is the choice of a blog topic on which I will write.

Wasting time on the internet?

Looking for something to read? Sorry, I'm running a mass to field calibration so that my isotopes appear at the correct apparent mass for tomorrow's visitor. I can't entertain you this evening. But if you're thinking you might want to do something vaguely useful to society, and you know something about geology (and I know a lot of y'all do), head over to Wikipedia's WikiProject Geology and see if you can apply your expertise to educating the world. It will be far more interesting than determining that mass 238.051 amu is centered in the detector when the magnet has a field value of 2219.269 gauss. Trust me. I'm thrilled because I'm starting at the top of the table and working down.