Why didn’t we figure this out before?

Weatherwatch: Did warm weather cause the Titanic disaster?

But in fact the catastrophe may have been set in motion by a warm, wet year over Greenland in 1908, resulting in greater snow accumulation.

Writing in the journal Weather, Grant Bigg and David Wilton of Sheffield University explain how the snow soaked through cracks in the ice sheet, encouraging excess iceberg calving over the following few years.

Soberingly, global warming has increased iceberg hazard greatly in recent decades, making years like 1912 more the norm than the exception.

The Guardian, 28 Apr 2014