Quantifying the Geophysical Causes of Present-Day Global Sea Level Rise

This project is designed to directly address The Ohio State University’s Climate, Water and Carbon (CWC) Project science question: “Does human intervention have the potential to push the climate system such that abrupt changes become more frequent, intense and rapid?”, through development of the interdisciplinary science of global sea level change. Global sea level rise is widely acknowledged to be one of the most important consequences of Abrupt Climate Change (ACC). The project is also relevant to the CWC objective of the quantification of the terrestrial surface water on Earth. Estimate of the surface water cycle imbalance due to anthropogenic warming and human-retention of water would help reduce the uncertainty of the global sea level budget. The 2007 Intergovernmental Panel for Climate Change (IPCC) report confirmed that anthropogenic warming has caused an accelerated sea level rise since the mid-19th century to the 20th century, with a present rate of 1.8 millimeters per year as compared to the rate of 0.1 millimeters per year during 1500–1900. Sea level rise is a measurable signal and has a profound social and economic impact. Quantifying, understanding and predicting the rate of sea level rise remains a challenge, because the signal reflects complex interactions among the solid-Earth and atmospheric, oceanic, hydrologic and cryospheric processes. While the IPCC study substantially narrowed the discrepancies between observations and geophysical causes of sea level rise, large uncertainties remain. The primary purpose of the proposed Core Project is to bring together experts to form a science team within The Ohio State University:

  1. to advance the interdisciplinary science of sea level change resulting from anthropogenic warming, and
  2. to develop an innovative cyberinfracture system for dissemination scientific of results to toad in mitigation of sea level rise hazards for the world’s low-lying regions.

This project will reduce uncertainties in the sea level budget and near-future sea level change by addressing the following open scientific questions:

  1. Can we resolve the controversy of whether there is a present-day (1990s–present) accelerated sea level rise, which would be an indication of anthropogenic warming?
  2. Can we explain, with high confidence, each of the plausible geophysical sources influencing sea level change, and reconcile with observed sea level rise?
  3. Can we better constrain the physical processes governing ice sheet sensitivity to climate forcing, to improve the prediction of ice-sheet contribution to near-future sea level rise under anthropogenic warming?

In addition to the improved estimates of Greenland and Antarctic ice sheet mass-balance, we anticipate a better quantification of thermosteric and halosteric sea level rise, pattern and magnitude of sea level change due to elastic loading effect due to present-day ice mass and fresh water imbalance on the ocean, rapid melting of mountain glaciers and ice caps, solid Earth glacial isostatic adjustment process and hydrologic imbalance including human impoundment of water. The proposed project is relevant and will collaborate with the Ice Core and Abrupt Climate Change, and Satellite Hydrology CWC Core Projects. Our anticipated results will reduce key global and regional sea level budget uncertainties and provide a quantification of each of the geophysical sources contributing to global sea level rise. Our coupling of detailed observational constraints and numerical modeling will improve our understanding of the mechanisms behind the dynamic response of ice sheets to climate change, to enable more confident predictions of the contribution of potential-rapid delglaciation of the Greenland and West Antarctic ice sheets to near-future sea level change. Our project will result in an innovative development of a cyberinfrastructure for improved result dissemination including software for quantification of sea level rise hazard for the world’s low-lying regions. Sea level and climate change is likely to be one of societal dominant concerns over the foreseeable future, likely resulting in expanded opportunities for external funding. The project will strengthen the scientific credibility of climate change research at The Ohio State University and enhance our ability to compete for external funding.

Funded by a core grant from the Climate Water Carbon Program of The Ohio State University.