Today we’ll look at the work being done by Dr. Grace Saba of Rutgers University. Grace is a postdoc in Oscar Schofield’s lab (remember the gliders) and is studying the effects of the dramatic increase of CO2 in the atmosphere.
She is doing a huge, tedious experiment to look at the effects of CO2 at 3 levels- 180, 385 and 750 parts per million CO2 (a percent is a part per hundred) which represent- a historical level pre-glacial era, today’s level and the level predicted to be reached by 2100. The first picture shows Grace in her lab performing one of the seemingly endless filtrations of the samples that she must do. The second and third pictures show the big cages of gas cylinders containing the CO2 mixtures and if you look closely you can see the tubes coming out of the cylinders feeding into the incubators where the gas mixtures are bubbled through the seawater samples and equilibrated. As atmospheric CO2 increases the dissolved CO2 increases and the acidity (expressed as pH) of the ocean increases (the pH decreases). Life forms are very dependent on the pH of their environment and Grace is studying what happens to the community composition of phytoplankton, bacteria and viruses as a function of the CO2 level. She is also looking at the effect on nutrients the plants and animals need to grow, as well as nitrogen uptake, and the effect of CO2 level on certain enzymes used by phytoplankton. Since all marine life is dependent on phytoplankton conversion of CO2 to energy and overall microbial activity- these are the food sources at the bottom of the food chain, changes in their activity can cause big effects on life further up the food chain. Grace is performing a very complicated experiment that will give much needed real-life data with regard to increasing CO2 levels and ocean acidification.
Palmer – 2011 Field Season, 24 January 2011. Article.