# Would the enthalpy of fusion for melting ice fields be a causative factor for colder winter weather?

Would the enthalpy of fusion for melting ice fields be a causative factor for colder winter weather?

As an example, NASA estimated the annual loss of the Greenland ice field 2002-2013 as more than 280 gigatons, and apparently increasing. Would the energy required for state transition on such a scale be a causitve factor in colder weather during a period of warming climate?

UPDATED: My wording above was too generalized and I got good answers to a question slightly different than the one I intended. Retry: According to Wikipedia, one of the vortices of the northern Polar vortex is Baffin Island, very near Greenland. The recent unusually cold weather in the eastern US has been attributed to the path of the Polar Vortex this year. My question should have been "could the energy required for state transition of the Greenland ice field contributed to the change in path of the Northern Polar Vortex this year?"

• My guess is no but I'm not a climate scientist so you'll have to wait for someone more knowledgeable to answer this. – bon Jan 19 '18 at 21:26
• Enthalpy of fusion? You're not talking about nuclear fusion I assume... Can you elaborate your question a little bit? – AtmosphericPrisonEscape Jan 19 '18 at 21:28
• This planet has succored life because of homeostasis. To have homeostasis there needs to be negative feedback systems, not positive. There is no way melting ice will COOL anything on this planet. And fyi, there is no global warming, has never been otherwise, we'd be a Venus. And mankind ain't going to be having any effect in any system any time soon. Except for leaving behind mountains and islands of plastic. – stormy Jan 20 '18 at 2:10
• atmospheric prison escape:"Enthalpy of fusion" is the term for energy required to be added to a system to change state from a solid to a liquid in the case of the icefields, from ice to water. It is also known as "latent energy of fusion". – youthwantstoknow Jan 20 '18 at 10:19
• stormy: melting ice cools things on this planet and any planet: that's how your old-time icebox works as well as your beer cooler. It – youthwantstoknow Jan 20 '18 at 10:23

## 2 Answers

The short answer is YES, but with a very important caveat. It won't be colder than usual, but colder than it would have been if the Greenland ice sheet weren't there to absorb that heat, and by a very small amount.

This is true for the mean global temperature, but when it comes to the actual strength of one winter season in a particular location, the atmospheric patterns play a much bigger role than the melting of ice sheets.

The latent heat (i.e. Enthalpy of fusion) of water is huge. The amount of energy needed to turn 0°C ice into 0°C water is the same as the amount required to heat up 0°C water to 80°C. Therefore, ice sheets and glaciers have a buffer effect on climate, as they are able to absorb a large amounts of energy without an increase in temperature.

Figure: Temperature curve of water as heat is added to 18g of water.

Despite of that, it is still a very small amount on the overall energy budget of the Earth, let's do the math:

280 Gt/year = 2.8e17 g/year
Latent heat = 333.55 J/g = 0.09 Wh/g
Total latetent heat = 2.8e17 g/year * 0.09 Wh/g = 2.5e16 Wh/year
That means a energy flux of 2.5e16/(365*24) = 2.8e12 W
Earth surface = 5.1e14 m²
Equivalent radiative forcing = 2.8e12/5.1e14 = 0.006 W/m²


Which is very small, in fact about a 0.4% of the radiative forcing associated to CO2 (see figure below):

The problem is that the resulting water have a impact in sea level rise and seawater salinity, that can in turn have an effect on ocean currents, deep water formation and other phenomena that can change the heat redistribution on earth. On the other hand, the reduction of ice sheets increase the albedo (because the bare ground absorb more energy than snow or ice), so that at the end the Earth will capture more energy leading to a positive feedback. Also, as the ice sheets get thinner, they will receive less snow (and more rain), therefore enhancing further reduction of the ice mass.

Finally, I have to add that when it comes to ice sheet models and climate models, the latent heat is always taken into account and if there were no latent heat, the figure for anual ice loss would be much bigger than 280 Gt.

Would the enthalpy of fusion for melting ice fields be a causative factor for colder winter weather?

No, for a number of reasons.

• Ice sheets melt in the summer and rebuild in the winter. This is winter.
• The enthalpy of fusion for water is 333.55 joules per gram. Multiply that by 280 gigatons per year and you get 9.3×1016 joules per year. While that sounds like a lot, it's a blip compared to the 5.5×1024 joules the Earth receives from the Sun every year.
• It's not a cold winter. While it has been an abnormally cold winter for the eastern parts of the U.S. and Canada, the rest of the northern hemisphere has been rather balmy. Nuuk, Greenland, for example, is suffering a heat wave. The current (06:38 UTC 21 January 2018) temperature there is 3°C (37° F), significantly warmer than average. The normal high for that location at this time of year is -6°C (24° F).

The melting of all that ice might well have an impact on climate, but it's the influx of 280 gigatons (and rising) of fresh water every year into the northern ocean rather than a paltry absorption of 1017 joules of energy every year that will be the cause.

• Thanks for your response, especially bullet 2! I was not aware that there currently was rebuilding of the ice sheets from the – youthwantstoknow Jan 21 '18 at 16:53
• news articles, so it is good to know! My thought had been that the melting might be enough to slightly change the path of the "polar vortex" bringing localized colder weather to areas not usually affected by it. – youthwantstoknow Jan 21 '18 at 16:58
• @youthwantstoknow - It still snows in Greenland, every winter. The ice builds up during the winter, melts during the summer. There currently is a net loss over the course of a year. – David Hammen Jan 21 '18 at 17:34
• @youthwantstoknow This animation will show the annual oscillation of sea ice over the past year... and this page will allow you to plot each year's levels to get an idea of changes through/between seasons. karstenhaustein.com/climate.php has some pretty decent looks at model/reanalysis estimate of temperature anomalies, including this plot for month to date. – JeopardyTempest Jan 21 '18 at 20:18
• It is small even compared to the warming of the oceans ~$10^{21}$ joules per year. – Keith McClary Jan 23 '18 at 21:11