Doctor Lee R. Kump, a professor of geosciences at Pennsylvania State University, has illustrated some disturbing parallels between the changes in global climate of today with a well-studied era in the planet's past. At that time, about fifty-six million years ago, temperatures worldwide rose some five degrees Celsius in the course of a few thousand years. This period is referred to as the Paleocene-Eocene Thermal Maximum (PETM). At that time in the planet's history the huge land mass known as Pangaea was in the final phase of breaking up into the current day continents. This process led to the formation of the north-eastern Atlantic Ocean. As a result, enormous volumes of molten rock were released producing intense heat. Carbon-enriched sediments that were close to the surface were subsequently burned releasing greenhouse gases into the atmosphere, especially carbon dioxide and methane. In addition, it is postulated that the concomitant warming of the ocean seabed led to the release of vast quantities of frozen methane.
The cumulative effects of these changes were the following:
- Marked increase in global temperatures (as noted above)
- Climate zones shifted towards the poles both on land and in the ocean propelling the migration of living things to accommodate this change
- Within the ocean depths, acidity increased and the supply of oxygen diminished killing of many organisms there.
These changes are striking similar to what is being reported currently. In regard to the status of the oceans, an international workshop, sponsored by the International Programme on the State of the Ocean (IPSO), has recently met in Oxford, UK. Their goal was to study the impact of human-made stressors including warming, acidification and overfishing on the overall health of the ocean. The conclusions this international group of experts reached are quite alarming. In essence, they have concluded that the stresses imposed on the world's oceans as a direct result of human activity may lead to "globally significant marine extinction."
In addition, Doctor Kump has determined from his studies that, in fact, "global temperature today is rising much more quickly than it did during PETM." If the current rate of increase in atmospheric greenhouse gases continues unabated, it is estimated that global temperature will increase by eight degrees Celsius by the year 2400. This kind of increase would profoundly and dramatically change the nature of life on the planet and drastically impact the possibility of continued human survival. This kind of change can only be averted by a global commitment to dramatic changes in human behavior and expectations. It should also be noted that it took some 200,000 years for the planet to cool down during PETM.