GSM Technical talk (in collaboration with the Geology Department, UM and Institute Geology Malaysia): “Why would sea-level rise for global warming and polar ice-melt?.” - Aftab Alam Khan (University of Dhaka)

Event Code : GSMTT 4-27-2017 Venue Name : Geology Department, University of Malaya Host Name : Coordinator Name : Date From : 2017-04-27

Talk begins at 5:00pm, tea will be provided at 4:30pm.

Two major causes of global sea level rise such as thermal expansion of the oceans and the loss of land-based ice for increased melting have been claimed by IPCC. On the otherhand, the climate threat investigation revealed that atmosphere–ocean modeling is an imperfect representation of the climate system, paleo-data consist mainly of proxy climate information usually with substantial ambiguities, and modern observations are limited in scope and accuracy. Here, my study shows that although global warming and polar ice-melt a reality but are not the potential components for the sea level rise. Polar sea-ice on melting can reoccupy same displaced volume of the floating ice-sheets, while polar land-ice cover on melting reduces load on the land activating elastic rebound of the crust that eventually raise the land to attain isostatic equilibrium in the polar region. Such characteristics can not contribute to the sea level rise. Global palaeo-sea level rise and fall in macro-scale (10 to 100 m or so) are related only to the geological events like converging and diverging plate tectonics, orogenic uplift, basin subsidence, volcanism, prograding delta buildup, ocean floor height change and sub-marine mass avalanche. Further, palaeo global sea level rise and fall due to the geologic events were not uniform and varied its pattern with global and local conditions. This study further reveals that geophysical shape, gravity attraction and the centripetal acceleration of spinning and rotation of the earth act against sea level rise.