Sea-Shore 193

 Then you don’t.

One of the advantages of living in the middle of a continent is, as oceans rise, we stay dry. That is not to say we won’t be affected, especially economically, by climate change but we are not faced with the morbid challenge hundreds of millions of people face as rising temperatures drive oceans up. The challenge being, “When do we move?”

How many people will be forced to high ground? How high will the waters rise? This number is what shore front property owners, port authorities, seaside power plants, city water and sewer planners, road commissions, and landfill operators need to know to meet the threat. Scientists are confident they can calculate how high the oceans will rise but there is one variable, one factor, they cannot figure out. Perhaps this variable is one only psychologists and sociologists can make an educated guess at. One factor only God knows. It is the warming limit being hashed out in Glasgow by the world’s nations. Will it be 1.5 C, 2 C, or 3 C?  Or, will the worlds collective will-power fail our children completely?

It is hard to imagine something as large as our oceans rising. I flew and sailed across them for seven years. They are immense. They make our beloved Great Lakes look like mere puddles.

The oceans have risen 7 to 8 inches since 1900. That is in 120 years. Alarmingly, half of this has happened since 1993 or in just 28 years.

The bottom line is man-made greenhouse gasses, which trap the heat from the sun, are the evil pollution responsible.

This heating, in turn, warms the oceans.  As the seas heat, they expand. The term used is “Thermal Expansion” and it accounts for nearly half the rise so far.

The other half is the melting cryosphere. The cryosphere is simply the land and water which usually remains frozen. Today much of it is melting.  The three melting sources pouring into the oceans are the world’s glaciers, the Greenland Ice Cap, and the Antarctic Ice Fields.

 The current rate of rise from thermal expansion and cryosphere melt is 3.3 mm per year, or .12 inches. If this rate were to remain steady, in ten years the oceans would rise 1.2 inches. In 100 years 10.2 inches.

But the accumulation of anthropogenic greenhouse gasses is rising. The prognosis is by 2030 the oceans will rise between 3.6 and 7.2 inches. That is if you do not include the recent Antarctic Ice Fields studies. If the Antarctic continental ice sheets destabilize, as some scientists suggest, sea levels could rise a catastrophic 6 feet by 2100.

Whether we hit 3.6 or 7.2 inches in the next decade, or 6 feet by the end of the century, it depends on what we do today. Scientists, politicians, and business leaders in Glasgow are negotiating policy. If they agree to a 3 degree Celsius (5.4 F) global temperature rise scientists calculate humanity will see an eventual leveling out at a 9.6-inch ocean rise.

If the negotiators can agree and implement aggressive policies transitioning to clean energy, the reward will be a limit of 1.5 degrees C, (2.7 degrees F), halving the ocean rise to less than 5 inches.

I think you can understand why coastal communities take climate change seriously. For us, increased temperatures will drastically shorten our winters, allow invasive insects with new diseases to spread north, destabilize our northern forest ecosystems, and will challenge our agriculture systems to feed us. But, it is not the same as going under water.

I’m praying the Lord will motivate the leaders in Glasgow to write strong policy. And, in turn, that our world leaders will be empowered with the determination to implement policy.

For our democracy these prayers, of course, include an informed, supportive, and brave citizenry.

This column is based on the SciLine report from the AAAS.  Which is the American Association for the Advancement of Science, the world’s largest general science organization.