The Sky Is Rising

Makarand writes "The height of the tropopause, the boundary layer between the troposphere and stratosphere and the roof of the Earth's lower atmosphere, has risen by an average of around 650 feet globally over the last 22 years according to this article in the San Francisco Chronicle. Greenhouse gases trap infrared radiation and warm the troposphere. The resulting tropospheric expansion is moving the tropopause upward. Also, the ozone depleted stratosphere is losing its ability to absorb sunlight causing it to cool and contract pulling the tropopause upward."

Comments

More Hail & Larger Rain Drops?

[ThOr101]

Wouldn't this also have an effect on hail, lightning and snow flakes? If these items are affected by travel within the storm, wouldn't a larger area of vertical travel cause hail to be more likely, lightning to be stronger (more convection space) and snow flakes to be larger?

All our weather happens in the tropopause yes, but doesn't it extend down into the troposphere where it hits the earth making the troposphere that much larger?

Also, if the tropopause is rising, does that mean the stratosphere is shrinking or rising? Is the whole atmosphere being pushed out? Is the jet stream rising with it?

Suppose this could mean higher expenses for air carriers, as they would need to climb to higher altitudes to get to the calmer stratosphere?

Of course

[SpaceLifeForm]

This is to be expected. Imagine the atmosphere as a balloon. If you heat it, it will expand. And not only that, but it's surface area will stretch and become thinner. Now imagine that the surface area of the balloon is the earth's ozone. There is only so much to spread around, and it becomes thinner and thinner. In the case of the balloon, it will pop of course, in the case of the atmosphere, it will re-organize itself in whatever state the laws of phsyics decide it should be organized. I.E, the ozone "hole". My point here is that the ozone "hole" can exist not just because of CFCs, but also because of Global Warming.

Re:Of course

[Alsee]

it's surface area will stretch and become thinner.

We are talking about something like a quarter-mile increase on a sphere with a radius of about 4000 miles. The "stretch factor" on the surface area and thickness is 0.0001.

There are some interesting and complicated effects going on, but a thinning of the ozone layer due to stretching isn't one of them.

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Re:Of course

[B.D.Mills]

We are talking about something like a quarter-mile increase on a sphere with a radius of about 4000 miles. The "stretch factor" on the surface area and thickness is 0.0001.

Your figures are incorrect because the earth isn't stretching along with the atmosphere.

The approximate shape of the troposphere *isn't* a sphere. It's shape is more like a solid of revolution formed by a thin annulus being rotated about its centre. (I don't know the name of this shape. But think of what shape an eggshell is if there was no egg inside it.) The troposphere is about 15-20 miles thick so an increase in thickness of 650 feet is more like a 1% increase. That's still small, but bigger than you thought.

oh the humanity!

[mcmonkey]

"Greenhouse gases, including carbon dioxide from the burning of fossil fuels, trap infrared radiation, warming the atmosphere. Santer and his associates believe that as the warming accelerates, the troposphere expands, just as a balloon warms and expands when it drifts from a cool room into a warmer one. Tropospheric expansion nudges the tropopause upward."

A more likely explanation, this is all a result of white people doing that "raise the roof" move.

Before everyone shouts global warming...

[Omkar]

try to remember we're just coming out of a frickin' ice age. The earth's temperature fluctuates, and not necessarily because of humans.

Re:Before everyone shouts global warming...

[PD]

It's been shown that at least some of the change is due to human activity, and we can't wave our hands and make that just go away.

Re:Before everyone shouts global warming...

[Mr. Slippery]

The earth's temperature fluctuates, and not necessarily because of humans.

People's heartrate fluctuates, and not necessarily because of caffeiene. However, if I just downed a triple espresso, and my pulse is now at 150bpm, it's a pretty good hypothesis that the drug is responsible, and common sense that if I don't want further increases I should cut back.

Re:Before everyone shouts global warming...

[jpop32]

try to remember we're just coming out of a frickin' ice age.

No, no, no... You got it wrong. We're just going into a new ice age. Global warming causes influx of excessive fresh water into the oceans (melting ice). Excessive fresh water in the Atlantic causes the Gulf stream to stop. With no Gulf stream to bring warmer waters to Europe, Europe freezes.

I suggest practicing winter sports if you're living in Europe. My plan is to relocate somewhere further south. :-)

Re:How do you locate the tropopause?

[GodsMadClown]

The tropopause is the boundary level, between the troposphere and stratosphere, at which temperature no longer falls as you rise in altitude.

As you move beyond the tropopause, into the stratosphere, atmospheric temperature will rise because the stratosphere contains more ozone. Ozone absorbs a significant portion of the UV light from the sun, adding energy to warm the atmosphere. Because atmosphere at these altitudes is much less dense, it doesn't take nearly as much energy to make changes in temperature. Because temperature rises with altitude, the stratospheric air is stable, with little vertical mixing.

What science is this based on?

[twfry]

Also, the ozone depleted stratosphere is losing its ability to absorb sunlight causing it to cool and contract pulling the tropopause upward

Um, the tempurature of the air above another layer of air does not contract or pull air below it up or down. The stratosphere's weight would be the same causing the same amount of force to be exerted on the tropopause. The tropopause's height is only effected by 1) its own temperature and 2) the compression force of whats above it.

Not so simple

[siskbc]

That's a good analogy, but the atmosphere is a good bit more complex than that. First, the atmosphere doesn't 'pop' like a baloon would - if anything it would keep getting thinner. Second, with more surface area where the ozone layer is shifted to, more ozone will be produced, which should counteract the effect.

But ultimately, the ozone hole occurs at the south pole for two specific reasons: First, the poles get a lot less radiation that the rest of the earth, hence less ozone production there. Second, the air currents over antarctica serve to trap the CFC's and ozone there DURING WINTER, allowing the CFC's to devour the ozone without it being able to re-mix with the rest of the atmosphere.

Note that this year the ozone hole actually shrank and split in half, due to a change in the weather patterns over antarctica. So I would be extremely hesitant to use a baloon analogy to explain the ozone hole - atmospheric chemistry is so hideously complicated.