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A bite on this? Some Friday Fodder...(15 posts)

A bite on this? Some Friday Fodder...rwbadley
Aug 9, 2002 7:40 AM
Here's a little food for thought.

An article in the paper today presented figures on the atmospheric temperature variation that occurred during the few days of 'No Flights' over the US during September of last year.

I was astounded that during 'no flights' the temperatures (especially over the east coast, where more flights take place) were both much higher (day) and much lower (night) than before and after 'no flight'.

This was in correlation to what the scientists had expected. The 'no flight' days gave them opportunity to test their hypothesis. This is just from contrails formed by jet flight!!

Sooo, (yes I am going somewhere with this) it can be shown that human activity can change weather patterns, and we could follow to the conclusion of climate change etc...

Right? ( I say this to those that doubt global warming or that humans have effect on...)

Now, We are all on this small planet together. What If a coalition of governments said "look here, what you are doing to our atmosphere (and water) is no longer to be tolerated. We have acid rain due to your emissions. Your pollution does not stop at your borders. You are using a weapon of mass destruction. We and our Children are threatened. You refuse to go along with this. We think it is time for a change in your leadership, and we will help you..."

Soo? Different?

Now I am not saying anything good about Saddam. His regime is obviously problematic. The trouble he creates generally stays within the borders of Iraq. We think he may support terrorism. This could have effect outside his border. This may effect others, ourselves and our children.

One scenario is different than the other. Hmmmm? Which one do you think is long term more dangerous to our grandchildren? Saddam will be gone. He can be made to go away.

What will OUR legacy be?

oh please...mr_spin
Aug 9, 2002 8:54 AM
Can there possibly be a more uncontrolled study? This is ridiculous. However you feel about the science of global warming, this is simply idiotic.

I'm supposed to believe that because no jets were creating contrails, temperatures rose?

Do you have any idea how hot jet engines are? A hot engine passing through the air should easily offset any cool temperatures generated by contrails.

Plus, what about all the jets taxiing, idling on runways, flying at low levels? Wouldn't all the hot air coming out of the engines raise temperatures? What about all the service vehicles, cabs, passenger cars, buses, etc. that weren't running as a result of no air travel. They all generate heat and emissions that should have raised temperatures. And yet, without them, temperatures rose? That makes no sense!!!
wait, so, now temperature extremes are desirable?TJeanloz
Aug 9, 2002 9:10 AM
I would presume that we are better off flying are jets and keeping the temperature from getting either too hot, which we all know will melt the polar ice caps and drown us all; or too cold, which will drop us into a new ice age.

What is the rest of the world giving us for providing the service of leveling out the temperature?
I agreeDougSloan
Aug 9, 2002 9:12 AM
There is an inherent problem in trying to ascribe causes to weather. With a hundreds years of partially reliable data and fluctuations over millions of years, we want to ascribe a cause to a few degrees differences here and there.

I'm sure everyone has considered the "heat island" effect, right? Also, have all measurements over the years been taken in the same locations? Geez, there can be 4 degree difference between my house and my office, 6 miles apart.

I agreeJon Billheimer
Aug 9, 2002 9:38 AM
A more accurate way to gauge global mean temperatures is ocean water temperature and ambient temperature a few feet above the water. Along these lines, apparently some errors were discovered from temperatures taken from ocean buoys, as the ambient temperature a few feet above them was significantly different than temps at the buoys' level. Which goes to show how difficult it is to gather meaningful global data. However, and possibly more telling, is the melt rate of glaciers the world over.
I agreerwbadley
Aug 9, 2002 10:15 AM
True enough, and if you have that data at hand you will see that glaciation advances and recedes over time. Generally, this would normally happen at a fairly slow rate, taking thousands of years. This does not seem to be the case, at present. Glaciation has been receding at quite a high rate compared to previous known records, and geologic studies.

The oceans, naturally, serve as a massive heat sink.
Study of ocean currents show very complex changes occurring in regional and global currents.

The contrail study was done by David Travis, atmospheric scientist at of U of Wisconsin. The desire for the study dated back to 1970's. The chance for implementation came last September. Temperatures taken were from over 4,000 weather stations across the US. Published in British journal Nature 8-(8?)-02.

14,000 flights over the continental US cause contrails to increase high altitude cloud cover which, it now appears, deflect or trap radiation causing cooler nights and warmer days.
The effect was most striking over eastern US. An apparent change in diurnal temperature range of 3 degrees C, or about 5.9 F.

I am surprised that nobody chose to follow my original post to a conclusion. If this data shows an effect so large from something we would consider to be a relatively small percentage of our 'contribution to the environment', then what about the larger balance of our actions?
I agreeTJeanloz
Aug 9, 2002 11:00 AM
In the first post:

"I was astounded that during 'no flights' the temperatures (especially over the east coast, where more flights take place) were both much higher (day) and much lower (night) than before and after 'no flight'."

In the second:

"14,000 flights over the continental US cause contrails to increase high altitude cloud cover which, it now appears, deflect or trap radiation causing cooler nights and warmer days.
The effect was most striking over eastern US. An apparent change in diurnal temperature range of 3 degrees C, or about 5.9 F. "

The first says that temperatures were warmer on the "no-flight" days, the second says that the contrails cause warmer days. I don't think both could be true at the same time. Could you clarify?

On the topic of 'our actions' this one data point hardly demonstrates a causal relationship between jet contrails and climate. But if we could prove it beyond a shadow of a doubt? I still don't think we'd care- we already burn most of the world's oil, and that doesn't seem to bother us.
Aug 9, 2002 12:32 PM
I apologize, the article read a bit strange in places. I think you will find the first post was correct, here is an official blurb from the website of Nature Magazine

Climatology: Contrails reduce daily temperature range


* Department of Geography and Geology, University of Wisconsin–Whitewater, Whitewater, Wisconsin 53190, USA
† Department of Geography, Pennsylvania State University, University Park, Pennsylvania 16801, USA


The potential of condensation trails (contrails) from jet aircraft to affect regional-scale surface temperatures has been debated for years, but was difficult to verify until an opportunity arose as a result of the three-day grounding of all commercial aircraft in the United States in the aftermath of the terrorist attacks on 11 September 2001. Here we show that there was an anomalous increase in the average diurnal temperature range (that is, the difference between the daytime maximum and night-time minimum temperatures) for the period 11–14 September 2001. Because persisting contrails can reduce the transfer of both incoming solar and outgoing infrared radiation and so reduce the daily temperature range, we attribute at least a portion of this anomaly to the absence of contrails over this period.

This, I read to mean that during 'no-flight' The temperatures were Higher during the Day, and Lower during the night, than on avg. of 'flight' days. The full text of the article was not available to me without subscription. If something as innocuous as a few contrails (well, 14,000 of them) gives the appearance of causing "an effect", then what of the other 92% of our actions?

Nature © Macmillan Publishers Ltd 2002 Registered No. 785998 England.
Aug 9, 2002 11:06 AM
I am no head in the sand "global warming is bogus" type, but the study is seriously flawed. It may actually be right, but no scientist or reasonable person could ever take it at face value. You can't take data from a moment in time and come up with meaningful long term projections. It would be as if you lived inside a cave for all of your life, but came out one day while it was raining. You might believe it was always raining outside, especially if you came out the next day and it was still raining.

I don't recall if air travel stopped worldwide during that time, and if so, for how long. I don't believe it did, even in the United States. Military jets were flying. Government jets were flying, transferring federal agents around. The United States and other parts of the world were closed, but not Europe, not South America, not Africa, not Asia. That's a pretty serious flaw in the study, because unless air travel stopped everywhere, you can't really derive too much from stopping it in one place.

Furthermore, ground traffic increased dramatically. People stranded in airports were renting cars and driving across the country to get home. People were driving their own cars more. There were more buses running. That's a lot of heat and emissions going into the air. Where does this guy account for that?

Finally, weather is connected all over the globe. Temperature fluctuations here, especially a one day change of 6F, would have a global effect. If this guy had done a usable study, he would have reported on what happened outside the U.S. What happened to offshore winds, for example.

It's nice to be an idealist, but don't believe everything you read. This study is an interesting project and nothing more. Funny how he published it overseas instead of here.
I have not been an Idealist in years, I'm afraid...rwbadley
Aug 9, 2002 12:52 PM
This was indeed based on a short window of opportunity.
I think the bigger picture is still being missed.

Weather is connected all over the globe. We, as occupants of this globe are connected to it's weather and each other in numerous ways.

The point I am trying to make is not so much about this particular article. It is just one of many similar you could go to and find if you dared.

The possibility of the new breed of Naval SONAR that uses ultra-low frequencies causing marine mammal disorientation and death is creating a stir. With the Navy intent on using this new SONAR over 75% of the earth ocean area, would we need to wait ten years until every marine mammal washed ashore to say "Gee, I guess there may have been something to it?"

Idealism has nothing to do with it. A concern for the direction of the species (ours, and others) is more aappropriate way to look at it.

Even an optimistic realist like myself has a problem with current events.

The Little Ice Age - When the Thames froze overjose_Tex_mex
Aug 9, 2002 11:17 AM
True, our data just does not go back far enough to make an accurate statement on climate.

However, I do believe we (Americans) need to cut back on our emmissions (cars ;-).

Perhaps, we are just going through a warm-up. In the 1600's the world went through a 70 year period of cold, known as the Little Ice Age. I believe the snow line, usually up in Canada made its way down around the Carolina's! I remember seeing a drawing of people walking and skating on the frozen river Thames.

Again, that was a natural occurring event. What we are doing to the atmosphere these days is just wrong. It does not take a lot to do a lot. One eruption from Mt. Etna (I believe) was enough to cool the entire planet by 1/2 a degree!
The Little Ice Age - When the Thames froze overgerwerken
Aug 9, 2002 5:21 PM
It is currently believed that the Little Ice Age was due to a giagantic volcanic erruption in South East Asia. Natural, yes. Damageing to the environmant, yes.

I don't believe that it is unreasonable to believe that long term emmisions output could have as much effect on the environment as an erruption. However the effect would be much slower to manifest because the pollution would build over years rather then being released all at once.

However I don't think that the only reason to reduce our effect on the enviroment is to avoid global catastrophe. If for no other reason protect the environment to enjoy it yourself. I like breathing clean air, seeing blue skies rather then haze, and comming out of the ocean covered in seaweed rather then paper wrapers.

Forget about our kids and grandkids. It is too abstract to deeply effect the emotions of anyone. Instead point out the field/lake/park/etc that (insert name) played in as a child, and is now used as a garbage dump/parking lot/timber farm/etc. It is not too hard to see our effect on the environment. It is everywhere.
Good point, since most often the furthest....rwbadley
Aug 10, 2002 8:32 AM
down the road we look is to the 'next election', I suppose considering a consequence (way out) to 30 years borders on ridiculous.

It is apparent that capitalism is a 'success' in regard to raising standard of living etc...
I think in the long term it would be doomed to failure considering the waste involved.

re: A bite on this? Some Friday Fodder...firstrax
Aug 9, 2002 10:38 AM
Maybe those two burning buildings fueled by thousands of gallons of jet fuel had something to do with it.
I wouldn't hang my hat on it.Steve98501
Aug 9, 2002 11:11 AM
I regard this as a piece of information, but far less than necessary to form any sweeping generalizations or conclusions. I do agree, however, that global warming is real and already is our legacy. I'm not an expert in that field, but I'm acquainted with a couple. Here's what one of them said in another forum just the other day:

"As an environmental research scientist myself (B.S. Chemical Engineering from the UW in 1984, I am the immediate past chairman of the Environmental Division of the American Institute of Chemical Engineers (the leading professional society for chemical engineers in the US -- and not exactly a liberal organization!). I've spent 18 years working for the US Department of Energy National Laboratories and for Private Industry on energy conservation, renewable fuels, and industrial pollution prevention) so I think I've gained some familiarity with environmental science. Everything in my training and reading of the scientific literature tells me that the net impact of industrial activity over the past 200 years has been to dramatically increase global CO2, and that the strong and growing consensus of the MAINSTREAM scientific community (not just the environmental fringe) is that average temperatures are rising as a result.

What is less clear, and where there is still a lot of room for debate and second-guessing, is in the analysis of the always important "so what?" question. Some parts of the world will certainly benefit from global warming (thinking long-term investments? Consider buying real estate in the Yukon!). Other parts of the world will certainly suffer as a result (kiss a lot of beach-front property in Miami good bye!). The vast middle remains a question mark -- though for those of us here in the NW, our best climate models predict that even with very modest average temperature increases, we will see wetter, warmer winters, lower snowpacks, more rapid spring thaws, leading to more of a flood/drought cycle in many area rivers.

. . . The bottom line is that there are economic reasons as well as environmental ones for reducing fossil fuel use, carbon emissions, and the like. The real argument will not be over whether we can afford to act, but over who will pay. Whether we do nothing or completely alter our economy to respond to the threat (or more likely, do something in between), SOMEONE will pay.

There's a reason that the global insurance industry has been leading the private-sector call for reductions in greenhouse gases. When coastal regions flood due to more severe weather and sea level increases, who do you think will be paying the claims??" Scott

The U.S. consumes more of the planet's non-renewable resources, and produces more non-recyclable waste per capita than anywhere else in the world. Using the statistics that support those conclusions, one could develop an argument that the U.S. is the planet's leading environmental terrorist; that even though we do more than any nation to protect the environment, we also do more than any nation to consume its resources and further degrade its suitability for human habitation. I'm not advocating that argument, I'm just agreeing that a strong argument along those lines is possible.