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- Stephan A. Klapp
Stephan A. Klapp
Report of GLOMAR PhD student Stephan A. Klapp about his research stay at Monterey Bay Aquarium Research Institute (MBARI) in Moss Landing, California, USA from 1 July - 30 September 2008
Stephan just returned from a research stay at the MBARI – short for Monterey Bay Aquarium Research Institute – in Moss Landing, California, USA, where he was working in Dr Peter Brewer’s lab. The MBARI is founded by the Packard Foundation and is the scientific arm of the Monterey Bay Aquarium in Monterey, California.
The Brewer lab at the MBARI focuses on ocean chemistry, in particular on the effect that greenhouse gases have on the chemistry of the ocean. Stephan and his colleagues at the MBARI looked at the gas hydrate crystallization from seawater and gas in the deep sea. The team was tracing the question how gas hydrates form in situ, how the surfaces of gas bubbles turn into hydrate and what effect different initial formation gases have on the crystallization of gas hydrates. To this end, Stephan and the Brewer lab developed an experiment, which could be set up underwater and could be operated by the manipulators of an ROV. The ex-periment comprised several steps: In the first step, tanks of free gas needed to release certain amounts of gas with different mixes into devices, where the hydrate formation could happen (the gas combines with sea water to hydrates). This was a repetitive step, as the group needed to recover gas hydrates at different time intervals after the reaction. Accordingly, the second step required to separate sub-samples of the reacted hydrates from the experimental set up and to leave sub-samples at the sea floor in a condition where they neither could decompose nor be removed by currents. In a third step other sub-samples were supposed to be recovered by the ROV in pressure maintaining devices. Days later, the ship and the ROV returned to the site to recover the sub-samples which were left behind earlier.
Another part of Stephan’s research at the MBARI involves Raman spectroscopy: He used the sophisticated laser Raman spectrometers at the MBARI to research pore waters for dissolved gases like methane and H2S. It turned out that the Laser Raman System is an excellent toll for pore water investigations, as the detection limit of a well-calibrated LRS is very low, and a quantitative assessment of the dissolved compounds is possible. Also, Stephan was involved in the development of new Raman system.
The Brewer lab at the MBARI focuses on ocean chemistry, in particular on the effect that greenhouse gases have on the chemistry of the ocean. Stephan and his colleagues at the MBARI looked at the gas hydrate crystallization from seawater and gas in the deep sea. The team was tracing the question how gas hydrates form in situ, how the surfaces of gas bubbles turn into hydrate and what effect different initial formation gases have on the crystallization of gas hydrates. To this end, Stephan and the Brewer lab developed an experiment, which could be set up underwater and could be operated by the manipulators of an ROV. The ex-periment comprised several steps: In the first step, tanks of free gas needed to release certain amounts of gas with different mixes into devices, where the hydrate formation could happen (the gas combines with sea water to hydrates). This was a repetitive step, as the group needed to recover gas hydrates at different time intervals after the reaction. Accordingly, the second step required to separate sub-samples of the reacted hydrates from the experimental set up and to leave sub-samples at the sea floor in a condition where they neither could decompose nor be removed by currents. In a third step other sub-samples were supposed to be recovered by the ROV in pressure maintaining devices. Days later, the ship and the ROV returned to the site to recover the sub-samples which were left behind earlier.
Another part of Stephan’s research at the MBARI involves Raman spectroscopy: He used the sophisticated laser Raman spectrometers at the MBARI to research pore waters for dissolved gases like methane and H2S. It turned out that the Laser Raman System is an excellent toll for pore water investigations, as the detection limit of a well-calibrated LRS is very low, and a quantitative assessment of the dissolved compounds is possible. Also, Stephan was involved in the development of new Raman system.