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This is the Ilulissat Icefjord.

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Miles upstream,

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behind millions of tons of floating ice, is
the Jakobshavn Glacier.

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And if the Greenland ice sheet melts,

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a good bit of the water will be coming down
this way.

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But a glacier isn’t a solid thing,

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it’s not some monolithic block of ice that’s
steadily melting.

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Glaciers flow.

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It’s a really counterintuitive concept,

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because most of the world is used to thinking
of ice in terms of frozen lakes,

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where the ice isn’t going anywhere.

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And let's be honest, this doesn’t look like
it’s moving.

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But glaciers aren’t static: they gain mass
by having snow fall on them,

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and they lose mass by a process called calving:

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the front falls off and generates a stream
of icebergs like this.

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Like a river, the glacier flows downhill.

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And the Jakobshavn glacier is one of the fastest
and most productive in the world:

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at the terminus, where the front falls off,

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it can move at 20 metres a day.

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And remember, that doesn’t mean the front
of the ice

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is moving towards us at 20 metres a day, just
that on average,

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the front bit of the ice is moving at that
speed

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when it falls off and forms these icebergs.

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If a glacier is gaining mass, it will steadily
advance,

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spreading out into the sea beyond until enough
of the front falls off

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that it reaches equilibrium.

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And if it’s losing mass,

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because there’s not enough snow, or because
it’s melting more quickly,

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it will steadily retreat.

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Remember, that’s not ice actually going
into reverse,

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it’s still flowing the same,

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it’s just that the point where the front
falls off is moving backwards.

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It's still producing icebergs.

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And the Jakobshavn glacier there?

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It produces a lot of icebergs.

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There’s a decent chance that the one that
sank the Titanic came down here.

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Now, I don’t want to debate climate change.

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Some very shrill people in the comments probably
will though,

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so I’ll say this: sure, the data is noisy.

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From the 1960s to 2000, the actual front of
the glacier here barely moved —

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and then in ten years, it retreated about
the same amount

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as it had in the entire 20th century.

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But climate change is about trends, not events,

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and if you don’t believe the enormous mountain
of evidence by now,

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then someone with no earth science credentials
talking into a camera in the Arctic

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isn’t going to convince you either.

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And part of the reason for that is that it’s
difficult to get across

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the sheer scale of what I’m seeing here.

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The camera can’t show you it.

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Even standing here in person,

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my brain is refusing to accept just how massive
everything is.

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And we're only seeing the 10, 20% of these
above water.

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Some glaciers will produce blocks of ice literally
the size of Manhattan.

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And yes, they’ll break up, yes,

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they’ll settle down to be something we’re
more used to,

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but like so many processes on our planet,

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this is on a scale that is pretty much unimaginable
to humans.

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It’s no wonder that the details of climate
change are difficult to understand:

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I’m standing here, watching the ice slowly
flow,

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and I still can’t get my head around this.

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I'm here with Chris Hadfield's Generator Arctic,
and so's she!

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Hello!

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That's Elmo Keep, she's writing wonderful
profiles

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of some of the people we meet out here.

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Follow her on Twitter to see when they're
published.

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Goodbye!