Dan’s Wild Wild Weather Journal

Admit it.

Sometime in the past you have complained that it always seems to rain on the weekend. In the back of your mind though, you told yourself that it really doesn’t rain more on any one day of the week.

Right???

WRONG! (If your in the Southeast U.S. anyway.)

Seems that a group of scientists decided to test a theory that it should rain more during the latter half of the work week than on the weekend. This makes sense because rain drops form on aerosols. (Aerosols include dust, sea salt, and soot etc. from air pollution.) More air pollution-more rain.

There was a famous paper (well in the geeky science world that I live in) about this affect about 30 years ago. The paper looked at rainfall downwind from St. Louis, and found that rain amounts were noticeably higher in Illinois to the East. Something the farmers there have for some reason decided not to complain too much about!

Along comes the TRMM satellite. The Tropical Rainfall Measuring Mission satellite was the first time we put a good old fashioned weather radar on a rocket and blasted it into low Earth orbit. There has been a ton of science coming out of this radar. Including a study by NASA using our ARMOR Dual Polarimetric Radar.

Thomas Bell of Nasa Goddard, and several other scientists have written a paper about using the TRMM satellite to track rainfall variations by day of the week. They found that indeed there is a signal. Wednesday and Thursday are wetter than Saturday and Sunday over the Southeast. Not only that. The opposite is true in the Atlantic Ocean, to the east of the S.E. USA.

This makes sense for two reasons. First, the air pollution will get pushed eastward by the prevailing westerlies. So the weekend will have more aerosols in the air over the Atlantic.More aerosols-more weekend rainfall.

Secondly, (A bit more complex) is the atmosphere must maintain hydrostatic balance. In other words if air rises up into thunderstorms over the southeast, it has to sink back down somewhere else to compensate. Therefore, the Western Atlantic should be drier if we are wetter. This phenomenon is very noticeable around hurricanes. You usually see very litte airmass thunderstorm activity outside the circulation of a tropical storm.

So yes, all that junk we spew into the atmosphere not only reduces the visibility, it makes it rain more. (Visibilities in the Great Smokey’s are less than half what they were 50 years ago!) Look on the bright side. The weekend is ever so slightly drier and sunnier!

I found the paper in pdf form on Doctor Bell’s website:

http://climate.gsfc.nasa.gov/publications/fulltext/Bell-etal_JGR_2008.pdf

NASA has a summary here: http://www.nasa.gov/centers/goddard/news/topstory/2008/midweek_rainfall.html

If Math scares you, use the second link.

Later,

Dan

If you’re reading this blog from North Alabama or Tennessee then you have likely never heard of of Dr. Karl.

He is a household name in Austrailia though, and well known to listeners of the BBC as well.

Karl Kruszelnici is one of the smartest people you will ever likely come across. A Phycisist, Medical Doctor, Biologist, and TV Personality all rolled into one. I listen each week as he answers questions about science on BBC Radio 5 Live. I always learn something new.

Dr. Karl makes Science fun & interesting! (Something I try to do every day on TV here in Huntsville-with limited success, I think!)

You can check out his very popular website here at ABC Austrailia.

Doctor Karl is on Thursday morning at 3am London time. That is 9pm Wednesday night in the U.S. Central Time Zone. You can listen live to Radio 5 on the BBC.

Do what I do though, download the podcast of the Up All Night program on BBC Radio 5. I hear it is one of the most popular podcasts online! Click the small image below to get the podcast. (I hope the BBC legal folks don’t mind my grabbing the pic)

The Ozone levels soared Friday. We hit 127 on the air quality index in Huntsville. We always get calls and emails from people on days like this who are confused. Didn’t they hear that the ozone was disappearing? Wasn’t that a bad thing? Now we are saying there is too much of it! What gives??

Actually they are right, ozone is a good thing. It is also a bad thing. Here is the scoop!

Ozone is Ozone, but we have two areas of Ozone on Earth. Tropospheric Ozone and Stratospheric Ozone.

Ozone is oxygen by the way. The oxygen we breathe is two oxygen atoms bonded together. Ozone is formed when three atoms of oxygen bond.

The stratospheric ozone is good. It blocks harmful ultraviolet radiation from the sun from making it to the surface. Tropospheric Ozone is bad. It causes allergy like symptoms and is bad for your health.

The bad ozone (near the ground) is formed from exhaust gases from burning coal and oil. sunlight interacts with these pollutants and through a photochemical reaction, Ozone is produced. Some of this ozone will make it to the stratosphere eventually, and become good Ozone.

One of the greatest success stories of international cooperation is the Montreal Protocol.  Scientists discovered in the 1970’s that chemicals used in air conditioners, and in aerosol cans were reaching the stratosphere and reacting chemically with the Ozone to destroy it. These CFC’s (Chlorofluorocarbons) were essentially phased out and replaced with more safe alternatives. This agreement is why you will have a tough time buying Freon these days! The Montreal Protocol has been amended a few times since 1985 to phase out other Ozone destroying chemicals as well.

Now the famous Ozone hole that develops in the Austral Spring each year over Antarctica is still there and bigger than ever, but atmospheric models now show that the Ozone hole will be mostly gone by 2065.

This is a good thing, in more ways than one! We did not appreciate it at the time, but it turns out that Ozone is a potent Greenhouse gas!

There is some significant new research coming out in August from NASA Scientist James Hansen. He apparently has evidence that Ozone, and some other pollutants have been responsible for more of the planet’s warming in the past few decades than thought.

Tropospheric Ozone is the reason we have an Air Quality Alert this weekend (July 2008) here in Huntsville.

The clean air act specifies that cities should try to keep Ozone levels below a certain standard. The current standard is 76 ppb (Parts per billion). It was just lowered from 80 ppb this year. When the air quality index is at 100, that indicates that the 8 hour average of Ozone was at 76 ppb. Friday’s number was 127, so we were well above the standard.

One last thing and perhaps most important. Politics is involved in this standard. The EPA has a Science Advisory Committee that advises the EPA on what level of Ozone is dangerous to health. The panel last year Unanimously recommended that the standard be lowered to somewhere between 60-70 ppb. The EPA lowered it 4 ppb from 80 to 76.

The EPA says an AQI number of 90 is moderate air quality. The top scientific experts say it is unhealthful. So what do I tell my viewers?? I am doing both.

The EPA is now proposing doing away with this science advisory committee. This proposal has met with some fierce criticism from the scientific community.

You may have heard me mention CoCoRahs on a weather cast a couple of times, and did not pay much attention. Well you should have! If you are the type of person who is interested in science (Why are you reading this if you’re not? You certainly cannot be expecting news about that Brittany person) then you really should check it out.

CoCo Rahs stands for community Collaborative Rain and Hail Study. What it boils down to is this. With the Internet, we can now collect very valuable rain, hail, snow data from across the nation in real time!

This is not only valuable to synoptic forecasters like myself, but to climatologists and hydrologists as well. Both now, and in the future!

It takes 5 minutes a day at most. Less if there has been no rain or snow. Best of all, you will have the good feeling of knowing that your making a valuable contribution to science!

You will have to fork out $28 for a rain gauge but that is the only cost. Just go online and type in your precip..hit submit and you’re done! The reason for the special rain gauge is simple. Your gauge is not accurate! Hold on you say. You have a $500 tipping bucket gauge running on solar power! Nope, the plastic CoCoRahs gauge is better. It is even better than the VERY expensive gauges that NOAA puts in at airports!

Have I talked you into it?? Check out cocorahs.org and look at the power point below!

Here is a link to a power point with tons more info:

The UK took a big step back from Biofuels this week. It seems the science has finally caught up with the rhetoric. Are biofuels all they are cracked up to be?

Maybe, but science tells us not the way we are headed now.

First of all let’s start with the basics.

The idea behind biofuels is a good one. The thought process works this way..

We grow corn which takes carbon out of the air and ground. We turn that corn into ethanol to burn in our gas tank. Yes, this will release Carbon back into the atmosphere, but we are just recycling it. The next crop of corn will suck the carbon right back out again.

Another benefit is that countries that use a LOT of oil are not as dependent on Middle Eastern suppliers. If we make enough perhaps we will not have to drill up the ANWAR and a thousand other places to supply our fix.

When we use gasoline (Petrol for you Aussies and UK folks) we are taking Carbon that was long ago taken out of the carbon cycle, and putting it back into the atmosphere.

This is not good because the more Carbon we put into the air, the warmer our planet gets.

It all looks good on paper but the devil is in the details.

When we calculate how much carbon we are saving with biofuels, we have to consider the energy needed to plant the crop. Fertilize the crop. Harvest it and convert it to ethanol. All that takes fuel! Burning that fuel releases carbon, and other pollutants into the atmosphere.

So what happens when you do the math?

The answer is you save about 10-15% of the carbon that would be released from just using oil like we do now. Congress loved the math so much, that last year they passed new requirements that increase dramatically the amount of ethanol we use over the next 15 years. The farmers love it because the price of corn has tripled in 3 years! How much of this rise is due to demand for biofuels is debatable, but a World Bank report released recently says a large amount of the price rise is due to biofuel demand.

While high food prices are a pain in the pocket book to most Americans, and Europeans, they are a pain in the stomach to many people in the third world. If you cannot afford to heat, you go hungry. This is a science blog, so I will leave the important moral issues for someone else. Let’s just follow the carbon.

THE SHOE DROPS HERE

It turns out that a lot of the corn now being grown around the world is being grown on land that was not cropland a few years ago. Therein lies the problem. When you turn an hectare of Prairie grass into a corn crop you release the carbon in that prairie grass, and some of the carbon in the soil into the atmosphere.

With high food prices around the world, there are millions of hectares of rain forest, grass land, and any other vegetation you can think of being plowed under to grow biofuel crops. Not just corn either, Palm oil is the reason that the topical rain forest in Indonesia is under attack.

When we redo the math, and add in the amount of carbon released by turning land already covered by vegeation into biofuel crops, a much different picture emerges.

It turns out that biofuels grown on converted land actually cause MORE carbon to go into the atmosphere. In some cases many times more Carbon! In some cases it will take hundreds of years to save any carbon from the atmosphere. A rain forest stores a LOT of carbon. Cutting it down to grow corn for biofuels will do much more harm than good.

In other words, if biofuels put more carbon into the atmosphere than oil- Better to use the oil!

The American Meteorology Society brought together some scientific experts on Biofuels recently in Washington. You can see their presentatons here:

AMS ENVIRONEMENTAL SCIENCE SERIES

(Scroll down until you see the biofuels image)

Right now every gallon of ethanol costs the taxpayer 50 cents in farm subsidies. So keep in mind that it is not as cheap as you might think.

So do we dump the idea?

No.

There is VERY promising research that will likely show us how to make biofuels in a sustainable way that does not increase the carbon in our atmosphere. Unfortunately, they may not prove very popular with the National Corn Growers Association.

The evidence is growing that we do not have a lot of time to figure this out. One of the top climate scientists in the world believes we are already out of time. NASA’s James Hansen believes we might have already passed the tipping point, and we can no longer avoid significant changes to our climate.

The river of science supporting climate change has turned into an avalanche. I work hard to keep up with the peer reviewed science, and I have to tell you the news is not good.

Later,

Dan

Update Sunday 13-07-08:
CBS London correspondent Mark Phillips has done a very good piece on Bio fuels. He actually puts it much more succinctly than I do!

http://www.cbsnews.com/stories/2008/07/12/eveningnews/main4255982.shtml