Global Temperature Increasing Fears Scientists

Global Warming and Climate Change (Image Credited to NASA)

Even if we stop pumping carbon dioxide into the atmosphere and limit global warming to 2 centigrade, a cascade of tipping points may result in warming of 4 or 5 degree of Celsius, warns a group of 16 climate scientists. With that would come additional sea level rise of between 10 and 60 metre.

For most of the past half billion years, the Earth has been much hotter than today, with no permanent ice at the poles; the hothouse Earth state. Three million years ago, as carbon dioxide levels fell, it began oscillating between two cooler states: ice ages with great ice sheets covering much land in the northern hemisphere and interglacial periods like the present.

If Will Steffen at Stockholm University in Sweden and his colleagues are correct, we might be on the brink of pushing the planet out of the present interglacial state and into the hothouse Earth state. This means that even if all our greenhouse gas emissions ceased and we managed to limit warming to 2 Celsius by 2100 – we are currently on course for 3 or 4 Celsius by then – warming would continue over the next few centuries. The group also argues that existing models underestimate warming by at least 0.5 Celsius, because they don’t include all feedbacks, such as less carbon being stored in oceans or forest dieback. As Earth warms, more will be triggered. The team stresses it is pointing out a risk that needs studying, not something that is certain to happen. Some climate scientists expressed scepticism at the claim, although others thought it was reasonable.