Courtesy of Barry Lefer

From: Barry Lefer
T1, March 14, 2006

Clouds at T1

Today is the first "wet" day at T1. We are getting flow from the Gulf of Mexico, or as the meteorologist Ben de Foy told me the air is coming from Texas. Since I am from Houston, this makes me a bit homesick. By "wet" day, I mean the relative humidity today have been in the range of 30-60%, whereas over the last two weeks it has pretty much always been in the range of 10-15%. It is amazing to me this changes the chemistry. As you can see we are seeing significant cloud cover for the first time. In addition, here at T1 we are seeing the highest levels of the hydroxyl radical (OH) and hydrogen peroxide (HOOH) of the entire mission. As you might guess, these two important atmospheric gases are related to how much H2O is in the atmosphere. Today we had some school kids from Mexico City tour our site and visit the scientists in the trailers. It was a nice visit and they had some good questions.

Take care. Barry

Photodissociation of the Hydroxyl Radical
Hydrogen peroxide - H2O2

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