What Will Happen if Arctic Sea Ice Loss Continues?
Climate change has been and will remain a key topic of discussion and concern for many people. For scientists, sustained study of Arctic sea ice provides one reliable measure of what the future may hold. Are we headed for warming or an ice age?
Two years ago, I wrote an article about what the loss of the Arctic Ice Cap would mean for the future of human civilization.1 I explained how an additional 2–3° Celsius of global warming inevitably will melt the entirety of the polar ice cap. That melting as evidenced by the previous four ice age cycles results in a rapid drop in the global mean temperature and quickly brings on an ice age. Now, for the first time, four geophysicists at the University of Bergen, Norway, led by Marius Årthun, have determined when different regions of the Arctic Ocean will become ice-free.2
A Coming Ice Age?
This paradox of global warming swiftly bringing on severe global cooling can be explained by the difference in sunlight reflectivity by Arctic surface ice, which is 60–70%, compared to Arctic surface liquid water, which is only about 6%. Hence, the disappearance of the Arctic Ice Cap implies that Arctic Ocean waters will absorb much more heat from the Sun. This extra heat will produce more water vapor in the atmosphere above the Arctic and circulation patterns will deliver this excess water vapor over the landmasses surrounding the Arctic Ocean. This means that instead of most of Canada, Greenland, and Siberia receiving snowfall equivalent to only about 10 inches of precipitation per year, they receive double or triple that amount. This excess snow, within several centuries, produces thick ice sheets over Canada, Greenland, and Siberia, which plunge the world into an ice age lasting 90,000–100,000 years.
Arctic Sea Ice Mass Loss Since 1750 AD
The logs and annals of explorers in sailing ships establish that virtually all regions of the Arctic Ocean were ice-covered before the advent of the industrial revolution even during the summer season. Satellite observations of Arctic sea ice cover began in 1979. These observations show that sea ice cover has decreased in all Arctic sea regions and in all seasons over the past 40 years.3
Credit: Marius Arthun et al., Geophysical Research Letters (December 6, 2020), doi:10.1029/2020GL090825.
Figure 1 shows the seven Arctic Ocean Regions studied by Årthun’s team. Surrounding the Central Arctic region are six Arctic seas. From top to bottom in figure 1 they are the Beaufort Sea, Chukchi Sea, East Siberian Sea, Laptev Sea, Kara Sea, and Barents Sea. These seven are those with the most complete historical records of ice mass loss. Årthun and his colleagues made a reasoned case that the ice mass loss in the regions they did not study—the Canadian Archipelago, Greenland Sea, Bering Sea, and Sea of Okhotsk—would be roughly similar.
Årthun’s team analyzed changes in the mass of sea ice, not changes in sea ice extent or area. From 1750 until the beginning of satellite observations in 1979, they determined the following loss of sea ice mass in the month of September, during which sea ice mass attains minimal levels:
| Central Arctic | 14% |
| Beaufort Sea | 36% |
| Chukchi Sea | 51% |
| East Siberian Sea | 34% |
| Laptev Sea | 50% |
| Kara Sea | 89% |
| Barents Sea | 95% |
In 2017, satellite observations established the following summer sea ice mass losses relative to 1750:
| Central Arctic | 31% |
| Beaufort Sea | 55% |
| Chukchi Sea | 76% |
| East Siberian Sea | 79% |
| Laptev Sea | 87% |
| Kara Sea | 98% |
| Barents Sea | 99% |
From 1979 to 2017 the mass of summer sea ice shrank by the following amounts:
| Central Arctic | 20% |
| Beaufort Sea | 30% |
| Chukchi Sea | 51% |
| East Siberian Sea | 62% |
| Laptev Sea | 74% |
| Kara Sea | 82% |
| Barents Sea | 80% |
The Kara and Barents Seas, which had been filled with summer ice, already are virtually ice-free. All seven of the Arctic Ocean regions studied by Årthun’s team experienced significant summer sea ice mass losses from 1750 to 1979, an average of 53%. The losses within just the 38 years following 1979 are just as significant, an average of 57%.
Årthun’s team demonstrated, however, that outcomes for winter sea ice mass losses have not been nearly as dire. From 1750 until the beginning of satellite observations in 1979, they determined the following loss of sea ice mass in the month of March, during which sea ice mass attains maximal levels:
| Central Arctic | 0% |
| Beaufort Sea | 1% |
| Chukchi Sea | 0% |
| East Siberian Sea | 0% |
| Laptev Sea | 1% |
| Kara Sea | 37% |
| Barents Sea | 37% |
In 2017, satellite observations established the following winter sea ice mass losses relative to 1750:
| Central Arctic | 1% |
| Beaufort Sea | 1% |
| Chukchi Sea | 1% |
| East Siberian Sea | 1% |
| Laptev Sea | 2% |
| Kara Sea | 45% |
| Barents Sea | 45% |
From 1979 to 2017 the mass of winter sea ice shrank by the following amounts:
| Central Arctic | 1% |
| Beaufort Sea | 1% |
| Chukchi Sea | 1% |
| East Siberian Sea | 1% |
| Laptev Sea | 1% |
| Kara Sea | 29% |
| Barents Sea | 29% |
All seven Arctic Ocean regions studied by Årthun’s team experienced measurable winter sea ice mass loss both from 1750 to 1979 and from 1979 to 2017. However, only the Kara and Barents Seas had winter sea ice mass losses above 2%. By 2017, both the Kara and Barents Seas had lost 55% of the winter sea ice mass that they had in 1750. Today, the Russian port of Murmansk and the Norwegian ports of Vardø and Nordkapp on the northernmost shores of Western Siberia and Norway are ice-free year round.
Projected Sea Ice Mass Loss from 2020–2100 AD
Årthun’s team used the latest and best global climate models, the Coupled Model Intercomparison Projects 6 (CMIP6) models, to determine for seven different regions of the Arctic Ocean the projected rates of ice loss mass in summer and winter throughout the 2020–2100 time period. They produced calculations based on two CMIP6 models: (1) the SSP585 model where it is assumed that any maintenance or expansion of the world economy will be sustained by fossil fuel energy sources, and (2) the SSP126 model where it is assumed that any maintenance or expansion of the world economy will only be sustained by non-carbon-based energy sources. They did not consider models where the world economy or human population is significantly reduced.
For the SSP585 model, the summer sea ice mass losses in 2050 and 2100 relative to sea ice mass that existed in 1750 are as follows:
| Arctic Ocean Region | 2050 | 2100 |
| Central Arctic | 95% | 100% |
| Beaufort Sea | 98% | 100% |
| Chukchi Sea | 99% | 100% |
| East Siberian Sea | 99% | 100% |
| Laptev Sea | 99% | 100% |
| Kara Sea | 100% | 100% |
| Barents Sea | 100% | 100% |
For the SSP126 model, the summer sea ice mass losses relative to sea ice mass in 1750 are as follows:
| Arctic Ocean Region | 2050 | 2100 |
| Central Arctic | 66% | 76% |
| Beaufort Sea | 89% | 98% |
| Chukchi Sea | 98% | 99% |
| East Siberian Sea | 98% | 100% |
| Laptev Sea | 98% | 100% |
| Kara Sea | 99% | 100% |
| Barents Sea | 100% | 100% |
What this means is that for the SSP585 model, the entire Arctic Ocean becomes ice-free in the summer by 2100 and nearly all the Arctic Ocean by the summer of 2050. By 2050, even the Central Arctic survives with just 5% of the ice it had in 1750. The Arctic Ocean winter sea ice mass fares much better.
Turning to winter sea ice, for the SSP585 model the winter sea ice mass losses in 2050 and 2100 relative to sea ice mass that existed in 1750 are as follows:
| Arctic Ocean Region | 2050 | 2100 |
| Central Arctic | 3% | 21% |
| Beaufort Sea | 2% | 11% |
| Chukchi Sea | 1% | 8% |
| East Siberian Sea | 2% | 8% |
| Laptev Sea | 3% | 15% |
| Kara Sea | 77% | 99% |
| Barents Sea | 77% | 100% |
For the SSP126 model, the winter sea ice mass losses relative to sea ice mass in 1750 are as follows:
| Arctic Ocean Region | 2050 | 2100 |
| Central Arctic | 3% | 4% |
| Beaufort Sea | 2% | 3% |
| Chukchi Sea | 1% | 2% |
| East Siberian Sea | 2% | 2% |
| Laptev Sea | 2% | 3% |
| Kara Sea | 68% | 71% |
| Barents Sea | 72% | 73% |
For the SSP585 model, the Kara and Barents Seas become ice-free even in winter by 2100. The other five Arctic Ocean regions preserve 79% or more of the winter ice mass they had in 1750. However, all seven regions, even in winter, are projected to lose some additional winter sea ice mass by 2050 and more by 2100.
For the SSP126 model, all but the Kara and Barents Seas are projected to preserve 96% or more of the winter sea ice mass they had in 1750. By 2100, the Kara and Barents Seas are projected to preserve less than 30% of the winter sea ice mass they had in 1750.
The leveling off of sea ice mass loss seen for both summer and winter in some Arctic Ocean regions during 2050 to 2100 is due to two factors. One is that researchers project so much sea ice mass loss will occur previous to 2050 that there will not be much more sea ice to lose. The other is that in both the SSP585 and SSP126 models technological advances may yield at least some decrease in carbon emissions during the 2050 to 2100 epoch.
Implications for the Future
So far, there has not been a significant snowfall increase over either Canada or Siberia, though an increase has been observed and projected to further increase over northwestern China.4 Apparently, we are not at immediate risk of the onset of the next ice age. However, Årthun’s team’s analysis does indicate that there is no longer any doubt that substantial sea ice mass loss has occurred in the Arctic and that this loss is likely to accelerate during the next 80 years.
A reconstruction of Greenland precipitation patterns during the past 8,000 years based on hydrogen isotope ratios in lipid biomarkers reveals why no evidence of an impending ice age has yet been observed but why such evidence may be soon forthcoming.5 This reconstruction shows that increased winter snowfall over western Greenland correlates with decreased winter sea ice in Baffin Bay and the Labrador Sea.
For five of the seven regions studied by Årthun’s team there has been no significant loss of winter sea ice mass previous to 2020 and little projected to occur until after 2050. Only in the Kara and Barents Seas has there been substantial loss of winter sea ice mass.
Årthun’s team’s projections show that for all seven Arctic Ocean regions studied using the SSP126 model, no significant sea ice mass loss occurred from 2050 to 2100. Again, this model calls for an economy sustained by non-carbon-based energy sources. However, all seven regions studied using the SSP585 model projected substantial sea ice mass loss during this period.
The lesson for humanity is clear. If we are to have any hope of forestalling the catastrophic consequences to our global economy and civilization that inevitably will result from the onset of the next ice age,6 we will need to sustain or grow the world economy according to the parameters of the SSP126 climate model. As I have demonstrated in my book, Weathering Climate Change, we can do better than the parameters set by this model. We can grow the world economy while we substantially reduce the burning of fossil fuels.7
Our canary in a coal mine is the status of Arctic winter sea ice mass. Any significant further loss of winter Arctic sea ice mass will alert us to the need for immediate major corrective action.
Årthun’s team’s research even has theological implications. Many Christians believe that Jesus Christ will rule over an economically blessed earthly global civilization for a 1,000-year period (Revelation 20:1–10). A forestalling of the onset of the next ice age by about a millennium due to a prudent human response is not scientifically ruled out.
Featured image: Arctic Sea Ice
Credit: Patrick Kelley, Creative Commons Attribution
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Endnotes
- Hugh Ross, “The End of Civilization As We Know It, Part 1,” Today’s New Reason To Believe (July 9, 2018), https://reasons.org/explore/blogs/todays-new-reason-to-believe/read/todays-new-reason-to-believe/2018/07/09/the-end-of-civilization-as-we-know-it-part-1.
- Marius Årthun et al., “The Seasonal and Regional Transition to an Ice-Free Arctic,” Geophysical Research Letters (published online ahead of print December 6, 2020), doi:10.1029/2020GL090825.
- Josefino C. Comiso, Walter N. Meier, and Robert Gersten, “Variability and Trends in the Arctic Sea Ice Cover: Results from Different Techniques,” Journal of Geophysical Research: Oceans 122, issue 8 (August 2017): 6883–900, doi:10.1002/2017JC012768; S. Close, M.-N. Houssais, and C. Herbaut, “Regional Dependence in the Timing of Onset of Rapid Decline in Arctic Sea Ice Concentration,” Journal of Geophysical Research: Oceans 120, issue 12 (December 2015): 8077–98, doi:10.1002/2015JC011187.
- Botao Zhou et al., “Historical and Future Changes of Snowfall Events in China under a Warming Background,” Journal of Climate 31, no. 15 (August 2018): 5873–89, doi:10.1175/JCLI-D-17-0428.1.
- Elizabeth K. Thomas et al., “A Major Increase in Winter Snowfall during the Middle Holocene on Western Greenland Caused by Reduced Sea Ice in Baffin Bay and the Labrador Sea,” Geophysical Research Letters 43, nol 10 (May 2016): 5302–08, doi:10.1002/2016GL068513.
- Hugh Ross, Weathering Climate Change: A Fresh Approach (Covina, CA: RTBPress, 2020): 193–8, https://shop.reasons.org/category/format/books/weathering-climate-change-a-fresh-approach.
- Ross, Weathering Climate Change, 199–218.