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Comment Re:Physical Basis (Score 1) 359

Climate models are projections. They show an expected outcome given certain inputs. They don't actually predict how much C02 or methane we'll emit. They don't predict volcanic eruptions. They don't predict aerosol emissions. Each of these has an impact on the climate.

The model can say "if we have a volcanic eruption of this magnitude at this lattitude then we should expect this result", but cannot determine whether, how many, or where we will get eruptions. Plugging real world events into models after the fact can bring them closely in line with reality, That's not a fault of the climate models.

Even still, they do a remarkable job of projecting global warming.

Comment Physical Basis (Score 2) 359

correlation is not causation

It's a little more complicated than that. The underlying mechanism involves the relationship between changing zonal mean temperatures and the strength and position of maxima in the mid-latitude westerly jet. The main condition for resonance is the formation of a zonally-directed waveguide for a particular zonal wavenumber k, which depends only on the wavenumber and the shape of the zonal-mean zonal wind (U) profile. Such a waveguide is present when a mid-latitude region of positive squared meridional wavenumber l2 is bounded by latitudes both north and south where l2 vanishes, inhibiting the dispersion of wave energy and trapping excited planetary waves in the upper troposphere (300–500mb). This can occur for zonal wavenumbers k=6–81,2, with the waveguide found at the equatorward flank of the subtropical jet at latitudes around 30–45N.

Such conditions are typically associated with a profile for U characterized by two maxima in the Northern Hemisphere, i.e. a double jet latitudinal structure. In contrast to a single jet, a double jet regime associated with a profile for U is characterized by a confined sub-tropical jet with sharp edges wherein wind speeds change rapidly with latitude3. Such sharp sub-tropical jets are highly effective waveguides30,31, a central requirement for QRA (quasi-resonant amplification).

The team here has isolated a specific fingerprint in the zonal mean surface temperature profile that is associated with QRA-favorable conditions. State-of-the-art (“CMIP5”) historical climate model simulations subject to anthropogenic forcing display an increase in the projection of this fingerprint that is mirrored in multiple observational surface temperature datasets.

Comment Now we know why models underestimated sea ice loss (Score 1) 279

This study may partly explain why models drastically underestimated Arctic sea ice loss: http://neven1.typepad.com/.a/6...

Possibly sea ice loss due to man made global warming is in line with projections, but natural variability causes the observed melting to oscillate outside of projections. If so we should see the melt rate slow over the next few decades.

Comment Re:Climate change deniers (Score 1) 401

. "there's no discernible change in the Antarctic at any time in the year

Actually, there is even a slight increase in the antarctic for many of the months!

something that may indicate a problem in the Arctic in 'summer months' (4 through 9) but not a huge deal in the 'winter months" (10 through 3)'

Summer months are important because of the ice albedo feedback.

It's an interesting & fun graphic I'll give you that, but it doesn't 'prove' anything in terms of any major concern.

I wasn't really trying to prove anything. Just show the data.

Sure it might provide support for these guys getting $500B of taxpayer's money to freeze ice in the summer.

I'm pretty sure they're not looking for funding to execute the idea. Just investigating options. They're physicists after all, not engineers. It seems pretty far fetched to try to refreeze the arctic, but some pie in the sky ideas may be required once things start to accelerate.

Comment Re:Market Forces Kill Coal (Score 2) 201

By market forces you mean the immense pressure Obama put on the industry, choking it under regulations while giving huge tax breaks to other energy producers? The "market" had nothing to do with this.

You think coal got the short stick over the last decade? Try finding a decent video rental shop these days. Thanks Obama.

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