Untangling my thoughts ...
I need to be clearer about my goals.
1. I want to pursue scientific research in graduate school. Broadly, to investigate how the Earth works: how oceans, atmosphere, and land interact.
2. I want my work to have a positive impact on the human relationship with the environment.
3. I would rather be a scientist with the power to influence environmental policy than a lawyer or a politician.
4. I am interested in human influences on nature, but I also believe that understanding the Earth's history (pre-humans) is crucial to understanding what is happening now, and to predicting what will happen in the future (in terms of climate change).
1. I want to choose a program at Cambridge for next year that will best fulfill my needs/interests.
2. I need to choose an advisor and a research project that will help me develop technical skills and gain a better understanding of paleoclimate and environmental research methods.
Right now, I am leaning towards a project that explores the Ge/Si ratio in continental runoff (rivers and groundwater) and in ocean water/sediments as a proxy for continental weathering. In other words, the goal of the project is to find out if this ratio depends on the break-down of rocks, physically and chemically. Another aspect of the work is to find out how plants affect weathering, and if there is an isotopic "fingerprint" that we can learn to recognize as a plant signal. If this is true, then we can "go back in time" by studying ancient sediments and their chemical composition. If we find a certain ratio of Ge/Se, and likewise if we can find that "fingerprint," then (hopefully) we could say something about how much the continents were weathering at certain times in the Earth's history. And also explain WHY (which is a big thing for most geologists ... they why of everything).
This work would be important because continental weathering rates strongly affect the amount of CO2 (carbon dioxide) in the atmosphere, which affects global temperature. If we can figure out what was happening in the past, then we have a better chance of understanding how the Earth's climate is changing now, and how it will continue to change in the future.