01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-04-0011 |
| Title of Abstract | The potential impacts of long-term changes in the tropical exports of oxygen and nutrients on ecology: a case study |
| Authors | Peter A. Thompson, Lynnath E. Beckley, Raleigh R. Hood*, Helen E. Phillips, Michael R. Landry, Ramkrushnbhai Patel |
| Organisation | University of Maryland |
| Address | 6019 Todds Point Road Cambridge, Maryland, United States Pincode: 21613 E-mail: rhood@umces.edu |
| Country | United States |
| Presentation | Oral |
| Abstract | Our oceans are changing, and the second International Indian Ocean Expedition (IIOE2) provided a significant opportunity to observe large scale physical, chemical and biological changes some 60 years after the original Expedition. Here we compare observations in 2019 with those made in 1963 along 110°E. Our comparison focuses on changes in the upper 500m with their implications for ocean productivity. We report a general increase in temperature and an increase in salinity at mid latitudes. There is strong evidence of more 24 Ͽt water at ~100m extending from the tropics to at least 25.5°S possibly associated with the increased tropical precipitation and strengthened Indonesian Throughflow. Important for regional ecology this water has lower concentrations of oxygen and increased nitrate. The intensification of this layer within the euphotic zone is hypothesized to support increasing primary and secondary production along 110°E and the west coast of Australia. Based on other reports of decreasing dissolved oxygen at relatively shallow depths, and its likely transport poleward from the tropics, we hypothesize the potential for a widespread increase in primary production across the subtropics. |
| Are you part of IIOE-2 endorsed project | yes |
| Endorsed Project Number | IIOE2-EP06 |
| Keywords | climate, temperature, salinity, oxygen, nutrients, plankton, IIOE-2 |
| For Awards | no |