Sunday, September 16, 2012

Weekend Links

8 comments:

galacticsurfer said...

I read the article but don't really get it, though it seems to explain the high pressure over Greenland plus the faster ice loss in the arctic and the global weather pattern changes due to atmospheric changes. Maybe you get it and can explain it in short? If it is a good basic model then it will be applied and explained in the pop sci press in short no doubt.

Still freaking out that my excel table of IJIS data shows 778000 less than 2007 record and loss in september at avg. of 24000 per day to date. According to Werther's comment on Neven's latest blog entry this may be due to water temps being above zero in north. Maybe this will keep up till October falling 3.2 million for IJIS. The thinness is no doubt to blame with wind pushing (new patterns due to Greenland highs explained above acclelerating loss?) the thin ice around, which are disconnected to one another in small blocks so satellite thinks they are a big block but are not so they tip over in the warm flows and melt apart as they get less and less dense(deep warm water still present from "Arcticane").

yvesT said...

Unrelated question to Stuart :

Is it correct to say that, below eia data indeed refers to crude and crude only :
http://www.eia.gov/dnav/pet/pet_crd_crpdn_adc_mbbl_m.htm

If yes the current increase in US prod comes from :
PADD 2 (tight oil in the bakken ?)
PADD 3 : gulf coast inshore and offshore

But seem to remember reading on TOD that GOM offshore was decreasing, so the increase in PADD3 is it mostly onshore ?

What is your view on 2 3 years crude US prod evolution ?

Michael Cain said...

The article on south-facing windows is a classic example of the problems systems analysts often face. There's a conventional wisdom, often embodied in rules, that's also simply wrong under a wider variety of conditions. I suspect that once a house reaches a certain level of efficiency, the answer to the question of "What's the next step?" will almost always be "Put up another solar panel, because the electricity can be leveraged in effective ways."

Stuart Staniford said...

Michael: Yes, my instincts are similar. The Passivhaus standard seems to me to be aimed at the wrong problem specification - what I care about is getting to net-zero carbon emissions and there seem to be a lot more and cheaper ways of getting there than Passivhaus.

Lucas Durand said...

The Passivhaus standard leaves a lot to be desired.

However, in my opinion, its value has been in creating an [arbitrary] energy performance benchmark - it has done a fair bit to motivate some within the industry to "push the envelope" (pun intended), especially with regard to air-sealing strategies.

Net-zero construction also leaves a lot to be desired as well. You can magine why when you think of suburban neighbourhoods populated with "net-zero" mcmansions.

Stuart Staniford said...

Lucas:

Point taken on "pushing the envelope".

However, I am of the view that suburban neighborhoods full of net-zero homes (of whatever size) would be excellent progress over where we are today.

Greg said...

How much do precipitation extremes change in a warming climate?

Abstract (broken up for web readability, emphasis added):-

"... The results are in good agreement with those derived from the Global Precipitation Climatology Project (GPCP) data by Liu et al., [2009], providing an independent verification for large changes in the precipitation extremes: about 100% increase for the annual top 10% heavy precipitation and about 20% decrease for the light and moderate precipitation for one degree warming in the global temperature. These changes can substantially increase the risk of floods as well as droughts, thus severely affecting the global ecosystems.

Atmospheric models used in the reanalysis mode, with the benefit of observed wind and moisture fields, appear to be capable of realistically simulating the change of precipitation intensity with global temperature. In comparison, coupled climate models are capable of simulating the shape of the change in precipitation intensity, but underestimate the magnitude of the change by about one order of magnitude."

Non-Dai evidence which points to increasing volatility in crop harvests.

Greg said...

Tyler Cowen's (irritatingly paternalistic) piece in the NYT on world hunger linked to a speech by Michael Lipton, a long-serving agricultural economist, about Africa south of the Sahara and north of South Africa. In that speech he said the following about the region:

* Urban drift is a myth. Rural populations are growing just as fast as cities.

* GDP increase has been mainly from mineral extraction, which is not a big employer.

* To date the food supply has grown by using more land, not from increasing yields. They are now about out of usable land.

* Industrial agriculture has lower yields than small-holdings in this region.

* Per the UN, the population is expected to double by 2050.

So, to avert a Malthusian catastrophe, the region has to start increasing yields, something it failed to do while the going was easy. It also has to do that by empowering women (the farmers) in their own communities, and reducing child mortality as water stress increases. All this while growing seasons become increasingly erratic.

Personally, I can't see a good outcome, because history, culture, and incentives are working against it. It's more likely that local political elites will see high food prices as a way to make money, by kicking small farmers off the good land and leasing it to foreigners (China, various Middle Eastern food importers).