Meltwater pulse 1A was a considerable post-glacial sea level rise of about 20 m in less than 500 years, perhaps just 200 years.
Period
The meltwater event occurred in a period of rapid climate change when the Holocene glacial retreat was going on during the end of the last ice age. Several researchers have narrowed the period of the pulse to between 13,000 and 14,600 years ago.
The pulse is framed historically between the Bølling-Allerød (B-A) interstadial and the Antarctic Cold Reversal/Older Dryas events.
Mechanism
Computer modelling, published in 2012, suggests that the collapse of the ice-sheet saddle between Canada and Greenland can explain the meltwater pulse. A 2014 study that examined dust released from melting icebergs onto the seabed of the Southern Ocean suggests a significant meltwater contribution from a collapse of Antarctic ice sheets.
Whether the pulse originated in the North or South, the event probably relates to the North Atlantic Deep Water thermohaline circulation which transports heat between the North Atlantic and the South Pacific. At different times research supported the pulse originating in the north or south but it is certain there was some component from both, and perhaps the majority coming from the north.
Sea level
The sea level is estimated to have risen at a rate of 37 to 65mm/yr - the pulse was much larger than current sea level rise, which has been judged to be in the region of 2 to 3mm/yr.
References
External links
- Meltwater Pulse 2B
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