To Melt or Not to Melt

The outer envelop of most operational weather forecast products is about 10 days. This is approximately the cutting edge of forecasting these days, and weather services would love to push beyond 10 days with some skill. It’s a huge challenge, as anyone who follows forecasts knows well. To add to the challenge, we are in Greenland, a huge and high chunk of ice sticking up into the northern hemisphere circulation pattern, causing disturbances to the general atmospheric flow. Greenland is also a place that has not been observed very well, and thus, is generally quite poorly represented in weather forecast models. With all of this in mind, the 10-day weather forecast from the “European Center for Medium Range Weather Forecasts” (ECMWF), which is one of the premier weather forecast centers in the world, tells us that there will be melt at Raven in 10-days from now. Warm air will blow up to our station from the southeast coast of Greenland. That would be very exciting for us as we are installing our station at Raven in hopes of observing a number of these melt events over the course of the summer. We have been making measurements at Summit Station for nearly 14 years now, but Summit is a location that does not melt very often. Before the last few years, Summit had only experienced melt a couple of times over the past 800 years! But then since about 2012 there have been a handful of melt events, a couple this year, one that year…. And some years none. It has been this increase in melt frequency at Summit that has motivated us to explore the mechanisms that drive melt of the ice sheet. And this has driven us to move further south and to lower altitudes. Raven station is one of those places. We are going there to observe the atmospheric drivers of melt and the implications of that on the snow-ice-firn system. Thus, the potential of a melt event in 10-days, even with a large forecast uncertainty, is exhilarating for us as we start to transition towards the installation phase of our project.