This is going to be a long post, because I'm going to share my thoughts on the subject, so I'll break it into numbered sections for simplicity of responding.
1. The main issue is that this temperature anomaly is going to worsen an already low ice thickness in the arctic. It's not about extent, its about thickness. The winter season helps to maintain thickness throughout the year so that in summer months thickness is maintained sufficiently that the ice which has been there for hundreds of thousands and millions of years (I believe the last time we had no ice in the arctic was several million years ago) of years is not lost. This balance is in the process of being lost, and 7C temperature anomalies almost ensure that ice thickness will be record low this summer.
2. THE PROBLEM IS NOT JUST THIS ONE ANOMALY but that we've been consistently at least 2 -4C above baseline all winter (maybe someone can correct me I dont have the data in front of me)- I don't have the data in front of me, but I've been watching it often enough to notice that 2017-2018 has been impressive in the persistence of arctic temperature anomalies .
3. we're currently at the lowest winter ice thickness and extent in thousands if not hundreds of thousands (perhaps multi millions) of years. This means that there will be even lower ice extent in the summer and its possible that we will have a repeat of 2012, but this time with much thinner sea ice. As a result, I would imagine it's likely to have almost no ice in the arctic this summer.
4. As a result, and because the temperature anomalies are higher than they've been in hundreds of thousands if not millions of years, I would anticipate run away melting of the Greenland ice sheets. This is in addition to having almost no sea ice. 7C temperature anomaly is not just a "wow that's big" it's a "wow that's extinction material". The current rate of temperature increase over the past 150-250 years is far faster than the Permian, which took thousands of years to reach something like 12C.
5. Lower albedo effects in the summer months due to a lack of sea ice combined with methane release, CO2 release, and warmer sea temperatures will all feed back on each-other and produce remarkably warm conditions in the arctic this year, and EVERY SINGLE YEAR IN THE FUTURE. This is not just a one time event, this is the new normal, and it's only going to get worse in an exponential fashion. Unless of course something is done to lower arctic temperatures back to baseline levels immediately.
6. This is going to be a very difficult year for the apes of planet earth, and I would imagine that the next 2-5 years, at this rate, will not be survivable for most of them.
7. Already, temperatures in the northern hemisphere in many locations are 10-30 degrees above where they should be and its affecting agriculture. I can only imagine what's going to happen if there's no ice in the arctic this summer (or within the next 5 years almost certainly) and positive feedback loops take over.
8. The US only has a few months supply of grains to feed its population, and many countries has ZERO reserves. Multiple billions do not have more than 7 days worth of edible food stored, the rest have less than 30 days, and only a very small fraction have more than 30 days worth of edible food stored. Billions of apes rely upon agriculture to function almost perfectly each year, and if for any reason even 25-50% of that agriculture is unable to be harvested there will be famines of epic proportions that will activate positive feedback loops in the fragility of civilization that will cause even more deaths and more chaos.
9. Once positive feedback loops in the climate combine with positive feedback loops in the fragility of civilization, the combined effect will be exponential and difficult to comprehend. A good example of the positive feedback loops in the fragility of civilization is what happened in 2008 - one bank collapsed, which lead to more and more banks collapsing until everything collapsed - this is going to happen again, and this time it's going to happen at the same time that positive feedback loops in the arctic are ALSO taking place.
10. If societal situations spiral out of control and economic slowdown occurs, you trigger the removal of global dimming which increases worldwide temperatures by something like .5-3C within 1 month or so. What this means is that GLOBAL DIMMING will be removed when civilization is unable to function and the economy begins to slow down - the slower the economy, the higher temperatures get as aerosols fall out from the atmosphere. This will just make things exponentially worse because this process only takes a few months at most, as most of the aerosols are removed from rain events. The loss of global dimming due to an economic slowdown would increase global average temperatures no less than .5C within a few months. I've read figures as large as 3C within a few months.
In short, positive feedback loops = extinction of large apes worldwide within a relatively short period of time of this message, IF nothing is done immediately to lower temperatures of the arctic.