27 July 2010

Weathering the Gulf cleanup: Providing better forecasts over water

Posted by koneil

Responding to the Deepwater Horizon spill in the Gulf of Mexico has required hundreds of ships and steady air traffic – both of which depend on having accurate weather forecasts to operate safely.

Unfortunately, meteorologists haven’t have the ability to track weather conditions as well over the water as they do on land, which can lead to less accurate weather forecasts.

Don Conlee

Don Conlee (photo courtesy of Texas A&M University)

To address that need, the National Weather Service asked atmospheric scientist Don Conlee to collect data while based on a small research vessel.

Over land, weather balloons carrying sensing devices called radiosondes radio temperature, humidity and pressure data back to forecasters as the balloons soar to the upper atmosphere. Radiosondes provide essential data used to create weather forecasts.

Conlee, an associate professor of atmospheric sciences at Texas A&M University just got back from two weeks aboard the research vessel Brooks McCall. There, he tested new ultraportable radiosondes over water, where they’re not usually used. These tests, conducted late at night – the only time they could get airspace — helped provide the weather data that would keep the vital research and clean-up operations going safely.

GeoSpace blogger Colin Schultz spoke with Conlee about his research and what life is like on one of the many research vessels responding to the worst oil spill seen to date.

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Q: How important are weather predictions to the work going on in the Gulf right now?

DC: There are many [projects] that involve [knowing] what the weather conditions are. The surface burns for example, I’m sure there are wind requirements for surface burns. There certainly are for skimming, there are limits to when skimming is very effective. There are air operations. There are just a number of things which are occurring at the surface which are relative to, and the conduct of which is entirely dependent on, the weather. Having accurate weather forecasts really helps the planning, and when you can plan, you can operate more efficiently.

Q: The response in the Gulf has been fast, it’s been big, there is just a lot is going on. Has this presented any challenges for you?

DC: I think so. The cycle of planning that you normally get to do for an at-sea science expedition is definitely not there. So a lot of things are learned on the fly, and for us our whole operation was about learning on the fly. We had brand new highly portable upper-air balloon equipment, and learning how to do that on the fly at sea was very interesting, and that normally wouldn’t be the case. Normally we would have prepared and done several launches from shore. I’m sure that applies across the board to a lot that’s going on.

Q: Access to the Gulf has been restricted due to security concerns and other reasons. Was there anything that you saw that stuck out to you?

DC: Well I think everyone who sees the scale of the response is impressed. There’s just a lot of work going on, which is why I’m sure that we have to keep non-official vehicles out of there, because it is just a massive effort. It is an incredible array of surface vessels and rigs and aircraft, and so you’re struck that, you know, certainly people are trying to do something about this.

Q: Can you give us a sense of what an average day was like aboard the Brooks McCall?

DC: Our real upper-air activity show started around 10:30 at night as we were preparing for the launch, going through our procedures and the step-by-step to set up the [equipment].  We would launch the balloon around midnight. The balloon flight takes over an hour to go essentially through the entire troposphere and then into the bottom of the stratosphere, to break what we call the tropopause. That could be 50,000 feet [15,000 meters] fairly easily. At the balloon’s height it could be -70 Celsius [-94 F]. It’s very cold up there at the tropical tropopause, it’s usually one of the coldest places on the planet. Once the flight is terminated – either [the balloon] would get so high that we would just need to get the data and terminate the flight, or the balloon would pop, whichever occurs first –that might be around 1:15 am or 1:30 am. Then comes the task of getting the [data]… sent off, and we were usually in bed by 2 or 3 o’clock in the morning, and that wasn’t so bad.

Q: Was there anything preventing you from doing any of your work?

DC: We would have liked to have been able to do some comparison launches [but] we actually were not able to arrange that because of some on-going operations… We wanted to be in heavy oil and do a launch, and then be out of the oil and do a launch only a few hours later [to investigate if the presence of oil affects weather conditions]… Remember, it’s not only the main vessels involved that we hear about on the news [that are in the Gulf]. There [are also] all of these ancillary support vessels that are out there on the water, the ones running the ROV (remote operated vehicles) etc. So they had to clear the area to do some seismic work, and that actually did prevent us from doing one science thing we wanted to do. So it was unfortunate we didn’t get to do that.

Q: Was there any day or event that was particularly memorable?

DC: Well on our first period out there was a very vigorous easterly wave, which is the main weather event other than tropical cyclones that passes through the tropics. I’m a retired naval officer so I’m used to some life at sea, but for the size of the vessel and the swells that were building up, we were moving around a lot.

I wasn’t sea sick, but a lot of the crew was. You have a lot of folks, first-timers at sea, doing some of the chemical analysis and biological analysis, and it was very tough on them. We were probably in eight-to-ten foot [~2.5-3 meter] seas, and a lot of that occurred at night, and it was really rough. We had a fine cook on the ship, but I think only five or six people showed up for dinner on the worst evenings during that easterly wave passage. It was very interesting trying to fill up a balloon on a pitching deck, and keeping it from popping, and just trying to think in the middle of the afternoon when things are pitching around like crazy. So that was memorable I think for everybody involved, and it was even memorable for me.

Q: Could you give us a give me a sense of the mood aboard the R/V Brooks McCall?

DC: It varies. Since we were there during one of the so far fairly uncommon bad weather weeks, that was tough. I think as a weather man I observe this. Every time there are grey skies it takes everybody’s mood down several notches. Bad weather, grey skies, burning flares, the smell of oil, oil in the water – that was I think a time when nobody felt particularly positive. But then contrast that with the second week that we were there: better weather, better news of the second cap being put on, progress being made, maybe a little bit less oil in the water, sun shining, and the mood is a lot better. I think it really waxes and wanes. Of course the ship’s crew is just very steady, because this is life for them. But the science crew is pretty steady as well, they want to do a good job and I think they keep pretty positive spirits.

— Colin Schultz, AGU Science Writer