The end of an interglacial period – or intermittent warm periods between ice ages – is marked by the total melting of the polar caps. Wiki: “Outside these [ice] ages, the Earth seems to have been ice free even in high latitudes.” From a scientific point of view, the current melting of the polar caps is consistent with Earth’s history and – moreover – to be expected.
There is an interesting relationship (see graph) between carbon dioxide (CO2), ice, water and vapor (or “greenhouse gases“).
Carbon dioxide acts like an accelerator for storing in dry ice (solid CO2) up to a certain temperature. Above that tipping point, carbon dioxide works as an accelerator for melting of ice (Nature, Phys, ScienceDaily). Carbon dioxide is mainly stored in oceans (93%), and only 0.04% in (greenhouse) gases.
The current interglacial period started 21,000 years ago. Initially, sea levels rose slowly but accelerated some 15,000 years ago until about 7,000 years ago (5,000 BC).
During these 8,000 years, the sea level rose by +120-140 meters, which is beyond human comprehension. In cultural legends, this period may have been “The Great Flood” (BBC).
The future melt down of all ice may cause a further sea level rise of some +70 meters to +80 meters. Compared to current sea levels, the “recent” Pleistocene interglacial highstand was 75 meters lower, but the older and warmer Pliocene climate was higher: +10 to +40 meters (BBC, Wiki). The current climate is the Holocene.
The +120-140 meter sea level rise wiped out ancient civilisations as humans typically build their cities (and harbours) close to coastal lines (BBC). This may explain why scientists still believe there was no advanced civilisation before 5,000 BC. Hence, the “sudden” emergence of the “first” advanced – and sea-faring – Sumerian civilisation is still a scientific “mystery”.
The Neanderthal survived for some 700,000 years including 8 Ice Ages until they were wiped out by viruses, carried by the influx of homo sapiens who arrived from Africa around 40,000 years ago (Guardian-2016, my 2015 blog). The fragility of our current society (eg, food distribution, fuel, internet, technology, water) may not even survive the start of a new Ice Age.
The high(er) amount of greenhouse gases in our atmosphere has already delayed the next Ice Age by some 100,000 years (Bloomberg-2016, CNN-2016, Guardian-2016, Independent-2016, NYT-2003). Indeed, every cloud has a silver lining.
Cold as Ice (1977) by Foreigner featuring Lou Gramm as lead singer
artists, artist 2, lyrics, video, Wiki-1, Wiki-2, Wiki-3
Note: all markings (bold, italic, underlining) by LO unless stated otherwise
Yo también disfruto de lo que ustedes tienden a hacer. ¡Este tipo de trabajo e informes inteligentes! Sigan con el trabajo increíble, chicos, les he añadido a mi blogroll personal.