Profile
We, with Dr. Catherine Head at Oxford and ZSL, have installed more than 50 instruments at forereef, patch reef, and lagoon sites that measure temperature, light, salinity, oxygen, currents, waves, and tides throughout the year. Some islands in the Indian Ocean Region experience rapid drops in ocean temperatures of up to 8°C with durations ranging from 10’s of minutes to several days. Other sites show consistently warm temperatures with short-term and annual ranges of less than 3°C.
We expect thermal adaptation to occur within the same coral species’ living under such different conditions, an adaptation that can be measured through genomic and proteomic analyses and that has relevance for thermal resilience under global ocean warming scenarios. Understanding which coral communities are likely to be the most resilient to future warming is crucial for the design of a protected areas network for the Indian Ocean Region.
I am also interested in net primary production on Chagos reef systems and am employing a unique flux gradient method to quantify net community respiration and photosynthesis. These instrument packages are deployed for 2-3 weeks and span multiple diurnal and tidal cycles.
A by-product of this measurement is an estimate of rates of net calcification and we are working with Chris Perry and his team to interpret results. The data collected will help answer the questions:
- Are reef systems net importers or exporter of food resources in the tropical ocean?
- What members of the community are most actively engaged in nutrient and resource recycling?
I first dove on a coral reef in Port au Prince harbour in 1968. The colours and marine life were unexpected, stunning, and bizarre. I found my passion for marine science and coral reefs early in life and have now dove all over the planet. That reef in Haiti no longer exists and the decline in reef health world wide continues. We have little time to learn the best methods to protect what is left but it seems to me to be a planetary imperative.
Biography
My Project
Other interests
I’ve long been fascinated by natural climate variability at decadal to centennial timescales as well as methods to distinguish man-made from natural climate change. I make use of archives of past climate change such as cores taken from large coral colonies, lake bottoms, fjords, and long-lived trees. My lab has produced near-monthly records of past changes in the oceans going back more than 500 years. We have an Indo-Pacific focus and examine long-term changes in climate pacemakers such as the El Nino/Southern Oscillation and Pacific Decadal Oscillation.
I’ve been working on climate change and its impacts in Antarctica and the Southern Ocean since 1982. I study how food is produced in the sunlit parts of the ocean-sea ice ecosystem and then is transported into the deep sea, sequestering carbon. I also look at modern and previous melt rates of the Antarctic Ice Sheet in order to put bounds on future rates of sea level rise under global warming.
My lab at Stanford designs, and builds sensing systems that measure rates of community life processes in the coastal ocean over timescales of minutes to days. In coral reef systems we determine both net community production of carbon and net community production of calcium carbonate. A net positive production of calcium carbonate is required for reefs to maintain their position relative to sea level, and in some cases even keep up with sea level rise.