A NASA scientist visiting New Zealand is voicing new concerns about the alarming rate in which massive tracts of Antarctic and Greenland ice sheets are melting.
Bob Binchadler, a NASA scientist who has been studying that part of the world for the past 30 years, told TV ONE's Breakfast programme this morning that the science world is becoming increasingly worried about the rate at which changes in sea levels are occurring.
"We are quite concerned, as a citizen of the world, because we are seeing changes at rates that we never imagined we would witness, but it is happening.
"There have been changes where sea level - which is a primary concern here as the ice sheets shrink - have gone up quite rapidly, but certainly, the few thousand years that humans have been on the planet we've never experienced anything like this."
Binchadler estimates that sea levels are going up at a rate of 3mm a year, which does not sound that significant, but he warns that as the increasing effects of global warming are felt, changes, and a rapid rise in sea levels, are only going to increase.
"That's what surprises us," he says.
"We expected to see less ice. Every time the world has warmed, there is less ice and the sea level goes up, but the rates of change now really alarm us and astonish us.
"In the case of the floating ice shelves, these thick, floating sheets of ice in the Antarctic peninsula, take thousands of years to form, and in some cases they are disintegrating, in literally weeks, so that's certainly not a natural process."
This, Binchadler puts down to global warming and climate change - he also believes there is little we can now do to stop it.
"It's unlikely that we can stop it," he says.
"A lot of this is locked into climate change that is certainly going to occur and continue to evolve over the next few decades.
"Our focus is what is going to happen this century, that's what policy makers and decision makers are asking us, and the best evidence we have and the best insight into the behaviour of the ice sheet lead us to expect that by the end of the century we are going to see sea levels at least one metre higher than today."