Now when the deniers say ...see nothing to worry about, we need to point out you cant just deny climate change science but accept ice trapping water science.

"It's going to Heaven and will never affect me", said every selfish Trump supporter ever.

So, to connect the dots here. The water is pooling in the ice and is not getting released to the ocean. Here's what is not getting mentioned, eventually that water has to go somewhere. The great question is when and at what rate. If it flows at a constant speed, then sea rise is gradual and over a long period of time with measured effects on the environment. If the rate of release is not gradual, but at a faster rate, or quite a bit at one time, then it becomes a whole different story. Sea levels rise at an incredible rate over a short period of time. The global environment is effected in many diverse ways; dumping massive amounts of fresh water into salt water at that specific location creates a damn, stopping the flow of the Gulf Stream. Resulting in drastic cooling of the Nothern Hemisphere. This already happening in Ireland, Northern Europe, and North Eastern Russia. Here's where it gets real dicey. Scientists can't make predictions on what will happen globally to the environment because there are too many factors and computers aren't fast enough to run such complex equations. They have the ability to forecast some of it, but just some of it.

Lets hope its going to the Hamptons and Miami Beach. Perhaps the expensive water front properties owners will realize what is happening.

As the planet warms, the water retained almost certainly will eventually flow into the seas. And when that happens, it won't be a couple inches of sea rise. It will be enough to drown the coastlines of the US and to annihilate a good part of low-lying coastal countries and their people.

We are told 3 millimeters of sea level rise per year with current warming, and at that rate and 400ppm CO2 in the atmosphere, approx 240mm or 10" rise by 2080. But CO2 ppm is still rising and the ocean traps heat, and we don't know how fast this heat going into deep ocean currents gets to the poles. If this heat migration resembles anything like the spike in temperatures in Alaska this past year, i.e. localized to one of the poles, we're all in trouble--something like the Laurentian ice sheet melt, even if it's just a couple of feet. The calculation data we need to know is the rate of change of sea level rise with rising air and ocean temperature, or even the rate of change with warming we already have, which is not going away anytime soon. And the melt-->porous hole-->ice data here is just one location. It's also possible that it's melt-->porous hole-->ocean flow along the fringes of the ice sheet. On the political side, why haven't TN congressmen pushed for a zero emission model with TVA. There is already hydro, and solar installation is now cheap. With the right incentives Feed In Tariff would work overnight. This would be near zero emissions and cheaper electricity. TN senators have actually supported legislation favoring the fossil fuel industry, and one is a former chancellor of the U. of TN. Maybe it's all that money from fossil fuel plutocrats, now including the Russians, designed to stir up racist resentment. With the data, wise policy is a carbon tax.

Some of the melted water may not be getting to the ocean yet, but (as some people noted) it eventually will. The big thing is the fact that there's so much melting. This melted water is much better at melting more ice than just the warmer air. So ultimately the water trapped in the glaciers is going to eventually produced increased flows into the ocean and perhaps in very large releases.

Where the water goes is important regarding deep ocean circulation. Last year NASA's former lead climate scientist published a paper titled Ice Melt, Sea Level Rise and Superstorms. In it he suggested that deep ocean circulation like Antarctic bottom water formation and the AMOC (part of which is known popularly as the Gulf Stream) are more sensitive to shut down from melt water coming off the ice sheets than previously thought. If the AMOC shuts down, which he says is possible this century, he said that the increased horizontal temperature gradient between high and low latitude regions of the N Atlantic would drive superstorms unlike anything we have today.

Gravity measurements through the GRACE satellites should respond to water mass whether liquid or solid (ocean mass and groundwater were also measured by GRACE whose mission ended in October after 15 years). So those loses from the Greenland ice cap should stand - correct? So my assumption is that models of melt don't correspond to gravity measurements - and these field studies have largely identified the problem. Otherwise, the field studies seem to conflict with the GRACE studies. So some clarification and better technical writing would be appreciated.

Thanks for combining fascinating photos and video (everyone should click to the 2015 article on the expedition) with a real but approachable scientific paper that goes into great detail both about their modeling and also on the methods they used to extract data from a host of satellites like GRACE, Terra, Suomi NPP, part of the great legacy of earth science observations done by NASA and NOAA over the last 5 decades. And any holding time of this water is better than huge masses of it entering the Arctic ocean where it could affect the thermo-haline circulation and the Gulf Stream (along with lesser known current that encircle the world). While some runoff is unaccounted for, what is obvious is that heat has entered and changed the ice pack. Water in ice contains 10x the energy of just warmed ice, so any cold winter may have limited impact on the ability of the ice pack to return to normal. The ice pack may stay warmer, even close to 0C which will subject surface snow and ice to sublimation and/or melting earlier in the spring. What new source of heat has entered the Earth's climate ? Fossil fuels which have also brought us excess wealth in the middle east which has fostered terrorism. I really wish Al Gore had been wrong, or that global warming would have followed low predictions instead of some of the highest. I was not expecting to see much in my lifetime .. maybe my grandchildren's. Maybe driving SUVs instead of compact cars for 15 years did not help.

The question is not where the water is going, it will sooner rather than later end up in the Arctic seas. The real questions are (1) Where will all this water have the most impact once it exits Greenland? and (2) What will all this fresh and cool water do to the oceans' circulations and the planet's climate? A few sentences in a comment can not begin to address these questions but the answers are pretty well known. Perhaps another NYT article?

Of course there are never earthquakes in Greenland. Imagine a block of ice two miles thick becoming slush in a matter of minutes.

You mean Manhattan will not be under six feet of water?? DARN!! Maybe the fact that the sun is in a predictable cooling cycle will now be factored in. Man has so little grasp of the enormous factors that change climate, and that man, in reality, is a small factor compared to the really big factors that affect the planet.

This yea, up north, very few polar bear moms returned with one year cubs - most returned with two year old cubs. That usually indicates that it was a bad year for sea ice and seal hunting. Now this and POTUS reducing the size of protected land. We are already doomed and we maybe hastening our own demise.

I saw a study that, if all that cold water falls off into the ocean, it will alter the ocean temperatures so that the weather patterns in Europe will be drastically different, causing the equivalent of a nuclear winter, mass migration, and basically another angle of all that climate change chaos that we keep hearing about.

Is the waiter actually remaining in the sheet or is it flowing into the sea at an unknown location? If it is in the sheet, at some point in the future it's going to be released, and possibly very abruptly. Too bad we have an anti-science GOP running things that won't fund more research.

" Two inches by the end of the century ". I would think the doomsday crowd will use this to say the sky is falling, however, there are naturally occuring warming and cooling periods the Earth goes through. Further , what is below the ice, the minerals and metals as well as carbon based fuels could be invaluable in the future as the population increases.

The article says that the "ice loss is estimated through gravity measurements by satellites." Can these studies distinguish ice from retained water? If not, doesn't this mean that the the satellite measurements are counting retained water as if it were unmelted ice?

The NASA glaciologist Eric Rignot said recently that one of the more important findings of the last decade in the paleoclimate record is that if we warm the planet just 1.5-2 degrees C above pre-industrial temperature--we are almost there--we are committing the system to 6-9m of sea level rise, a large fraction of which could arrive this century. (At the current acceleration rate of 44 Gt/yr2 we get 78cm by 2100, thermal expansion and mountain glaciers another 20-30cm). 
Probably the most respected glaciologist in the US, Richard Alley, has said that Antarctic Ice Sheet mass is likely controlled by the temperature of the water at the grounding line of marine-terminating glaciers. Parts of Antarctica are minus 50 degrees C, warm it up to minus 45 and big deal, but it is at the melting point at the coast where thinning ice shelves provide less and less friction to ice sheet flow. 
A rise in temperature of just 1 degree C took out Jakobshavn's ice shelf in Greenland and is a big insult to an ice shelf almost anywhere on the planet. We know we’ve already put a lot of heat content into the ocean and not only are we warming the ocean, but increased westerlies due to global warming are apparently moving already warm water into contact with Antarctica's ice shelves.

The article suggests that if Greenland's ice sheet is absorbing some of the meltwater this would slow sea level rise. Greenland sits on gnarly bedrock so glaciologists don't see how it can dump a lot of ice quickly into the ocean. They are much more worried about West Antarctica because it sits on reverse-sloped, submarine basins up to 2.5km below sea level where it is bathed in warming water. The 120km wide Thwaites Glacier in West Antarctica can drain 3.3m of sea level rise equivalent of ice (although its basin and surrounding basins only drain around a meter’s worth of ice, the rest of the ice sheet gets hit from behind). Ice cliffs appear to fail when they are over 100m in height and when Thwaites backs up of its stabilizing sill it’s going to try to make an ice cliff 4km high. When the top of an ice cliff falls off the bottom lifts and breaks off. When the bottom melts the top collapses. Notch it in the middle and they both fail. Hence Marine Ice Sheet Instability or rapid and irreversible retreat.

Interesting that Boston has experienced two ‘king tides’ this month, with flooded sidewalks along the harbor. This is something never seen until recent years. As seas rise more, this flooding will encroach on some very expensive real estate. How much will it cost to build flood gates to protect major cities around the world? Maybe the one percent will donate their tax refunds.

If the melt-water is being retained in the ice sheet, this could indicate a delayed sea-level response. When the part of the ice sheet holding that retained water melts, it will release more water than it would have otherwise. Will be interesting to see how this research develops.

"Greenland’s ice sheet may grow in 2017 "For at least the past seventeen years (since probably 1996, according to recent publications) the Greenland ice sheet has been losing ice on an annual basis. This is best illustrated by data from the Gravity Recovery and Climate Experiment (GRACE) satellite, which measures the change in mass over the entire ice sheet through changes in Earth’s gravitation. Some years, such as 2012, have much larger losses, and others like 2013 lost little, but every year in recent decades has had at least a slight net reduction in ice. Overall the trend has been 286 ± 21 billion tons of ice per year, equal to about 0.8 millimeter sea level rise (0.03 inches). However, the events of the 2016-to-2017 annual snowfall and melt cycle suggest that this year will see a net gain for the ice sheet." --National Snow and Ice Data Center, Sept. 1, 2017 http://nsidc.org/greenland-today/2017/09/late-summer-melting-spike/