2015 is hotter than 2014, enough to break that record. More blowholes, extreme record acreage of forest fires in the northern latitudes, & more days of higher methane.
Can humanity stop it ?
The logistics of rapid decarbonisation is getting worse, while the odds fall below 50% by 2024, or sooner. With so much denial still going on and overpopulation nearing the massive economic depression point, it is unlikely humanity will stop what the once stoppable overpopulation has wrought, with greed. General stupidity/ignorance, along with increased lack of foresight have brought us to the point of starting the open ocean warming to runaway. Historical, geologically, evidence indicates tundra methane self release over +1.5*C and well below 2*C, to initiate methane turnover. This is from PETM, with its very long recovery time, and it wasn't even a true ELE with a 30% extinction.
This is similar in some ways and not in others, to what has been measured so far. Such as now being an increase in CO2 40 times PETM, and a heat rise (before tundra methane self release) 10 times PETM. In addition to double the ocean acidification in the geologic record, something even the Permian Great Dying did not have, with its methane turnover resulting in a 95% extinction.
I know there is at least 10% more sequestered methane hydrate than PETM and at least 20% more than the Permian. The turnover in each other case, stopped at a percentage of methane release below 100%, or the deep ocean deposits. Permian 70% and PETM 50%, in my estimation. A 10*C and 8*C temperature rise. It is possible that clouds blocked further deep ocean warming, with axis and orbital influences.
If it goes to 100% methane release, followed by CO2 from baked earth, then it is the Venus Effect. Otherwise, if it stops at a similar to Permian Extinction with more loss from acidification, it could be a 30 million plus year recovery from a greater than 95% extinction. That is actually the best case scenario, unless there is Divine Intervention.