And the Oceans Riseth

First in a series of articles about the current and future impact of The Warming on Mexico

BY LORIN R. ROBINSON, PhD

Some 65 million years ago, the Earth lost 75 percent of all plant and animal species during what is called The Fifth Mass Extinction. The land now known as Mexico was at the epicenter of the cataclysmic event that caused the global disaster. A massive comet or asteroid 10-15 km (6 to 9 mi)-wide smashed into the Yucatán creating a 180 km (112 mi)-wide crater christened Chicxulub.

The global environment was devastated, mainly through a lingering “impact winter” that halted photosynthesis in plants and plankton, killing animals and marine life right up the food chain—including dinosaurs, the apex creatures of the Cretaceous period.

That was the last “extinction” of any magnitude.  Until now.

It is widely believed that The Sixth Mass Extinction is underway—an ongoing event resulting from human activity. In short, global warming.

The term “global warming” can be misleading. Temperature and sea level increases resulting from greenhouse gases are global phenomena. But their impact is local. Global warming is and will affect every nook and cranny of the Earth and all its creatures large and small.

What is and will be global warming’s impact on Mexico, the place where the last extinction began? This investigative series asks and attempts, at least partially, to answer that question.

According to Genesis 7:21-23, The Flood inundated the Earth:

“All flesh that moved on the earth perished, birds and cattle and beasts and every swarming thing that swarms upon the earth, and all mankind; of all that was on the dry land, all in whose nostrils was the breath of the spirit of life, died ….”

Climate scientists today are not predicting a flood of that magnitude. The consensus is that the planet’s oceans will rise at least 1.8 meters (6 feet) by 2100. 

But other scientists paint an even more devastating scenario. As humans continue to pump 35 billion tons of CO² into the atmosphere annually, accelerating the melting of the globe’s huge glaciers and ice sheets faster than predicted, and gigatons of CO² are being released from the Arctic’s rapidly melting tundra, they say the oceans will rise more quickly and to a higher level than thought possible only a few years ago.

Item:  The last time the Earth saw more than 400 ppm of CO² in its atmosphere—800,000 years ago, according to the geologic record—its seas were 100 feet higher than today. The current CO² level is 409 ppm and rising.

It’s been relatively easy to blow off concerns about oceans swallowing the land. To date, we are told they’ve only risen by 20 centimeters (8 inches) since 1900, the benchmark. But imagine 20 centimeters of water in a bucket. Then imagine the number of buckets it would take to raise the level of the oceans—71 percent of the Earth’s surface—by that amount.

And the planet’s huge concentrations of ice have just begun to melt in earnest.

The overflowing oceans will affect Mexico as much or more than most countries.  We have 9,330 kilometers (5,800 miles) of coastline—13th longest in the world—stretching along the Pacific, the Gulfs of California and Mexico and the Caribbean.  Many of our 122 cities in excess of 100,000 population are situated on the coasts. 

Fortunately, major population centers such as Mexico City (12.3 million) and Guadalajara (5 million) are not coastal cities.

Should the ocean level increase to predicted levels by 2100 —and there are other more aggressive estimates—over 10 percent of the planet’s coastlines will be inundated.  In other words, 10 percent of its landmass will be flooded, made uninhabitable; the oceans would increase from 70 to 80 percent of the Earth’s surface.

Obviously, the increasing level and deteriorating conditions of seas that surround Mexico are crucially important, affecting its coastal cities, its tourism, its ports, its fisheries.

It doesn’t take much to imagine the impact of an additional six feet of sea level. But modeling by the U.S. National Oceanic and Atmospheric Administration (NOAA) depicting sea rise scenarios on U.S. coastlines—from one to 10 feet—leave little to the imagination. 

For a graphic and frightening depiction of the impact of ocean-level rise on a coastal city built essentially at sea level, look at Miami. Unfortunately, such modeling has not been done for Mexico.

What are some widely-accepted, common-sense predictions about the impact of increasing sea levels on our coasts?

    •    Mexican coastal cities, especially those essentially at sea level like Miami, will lose their beaches and, depending on the land gradient, their malecons and many blocks of prime real estate in their commercial districts. The impact on the viability of those cities over time will be severe. And the economies of those heavily dependent on tourism will be decimated.

    •    One of the least-considered effects of the warming is the inevitable migration of hundreds of millions around the world seeking safe haven from rising oceans, drought, desertification and violent weather. Research indicates most people will seek refuge in their own countries. Where will Mexican migrants find shelter?  “Although the exact number of people…on the move by mid-century is uncertain, the scope and scale could vastly exceed anything that has occurred before.”

    •    Rural coastlines will also be affected in ways too numerous to mention. Erosion can be expected.  Coastal regions—Yucatan, for example—currently protected by mangrove swamps will lose that protection when inundated by the Caribbean and poisonous salt-water incursion. The Yucatan government attempted to protect its mangrove swamps from human degradation in 2010. But that law can do nothing to halt the rising sea level.

    •    Twelve major rivers in Mexico empty into its surrounding gulfs, sea and ocean. Ocean-level increase will also raise the levels of these rivers, increasing the likelihood of flooding in towns along their banks. And saltwater will be forced farther and farther up their courses, contaminating freshwater resources. The negative impact on riverine ecology will be severe.

    •    Not only is the warming rising sea levels, but it’s also contributing to a tourism nightmare.  The mayor of Quintana Roo estimates that tourism has dropped as much as 35 percent because of sargassum seaweed washing up on its otherwise pristine Caribbean beaches. While not the sole cause, the warming of the oceans is a major contributing factor. For the record, tourism today accounts for 8.5 percent of Mexico’s GDP—246 billion pesos (15.5 billion dollars).

    •    Mexico has the 13th largest export economy in the world. That, of course, means the viability of its ports is crucial. Its five major ports, ranked by tonnage, are Manzanillo, Lazaro Cardenas, Veracruz, Altamira and Ensenada. Clearly, Mexican ports will need to spend billions to modify infrastructure to offset the impact of ever-increasing water levels on their operations.

    •    As will be discussed later in the series, hurricanes in the region are increasing in number and severity. The impact of hurricanes today is serious enough.  As ocean levels rise, however, their power to inflict phenomenal coastal damage through gigantic storm surges also increases.  Measuring the height of surges is difficult, but when Katrina slammed into the Mississippi coast in 2005, it is said to have produced a 28-foot surge that literally swept away the coastal community of Pass Christian.

    •    The condition of the bodies of water surrounding Mexico has direct an impact on the health of its fisheries. Fishing and aquaculture in the 17 coastal states produced an average of 1.5 million tons per year, 2006-2014. The highest profit, obtained in 2014, was 23 billion pesos (1.15 billion dollars).  While harvesting surrounding marine life is not a major contributor to the nation’s economy, it provides income for many thousands and is a major tourism attraction.  And, as agricultural conditions worsen, sea life could become an ever-increasingly important source of food.

Which brings us to the warming’s “equally evil twin.”

Ocean acidification, called the warming’s “evil twin” by climate scientists, is caused by CO² from the atmosphere dissolving in its waters. This rapidly increasing acidity is as, or perhaps more, harmful to the future of marine life than the overfishing practiced off Mexico’s coasts and around the world.

For a full and frightening forecast of the future of the planet’s oceans, see Chapter 6 in the New York Times Best Seller The Sixth Extinction (2014) by Elizabeth Kolbert. 

Kolbert notes that by the end of the century—if we don’t slow or stop trashing the atmosphere with greenhouse gases—ocean acidity will be 150-times greater than at the start of the Industrial Revolution. And many marine creatures—from the bottom to the top of the food chain—will simply not have time to adapt. The result? An oceanic kill off comparable to that facing terrestrial creatures.

(Watch for the second in this series - "Hotter and Dryer”)

About the Author—Dr. Lorin Robinson is a journalist, journalism academic and seasonal resident of El Sargento-La Ventana, Baja Sur.  He has written extensively about the warming. His latest book on the subject is Tales from The Warming (2017).

"This is the first in a series of four articles investigating the present and future impact of The Warming on Mexico.  Let us know if you'd like to see the rest of the series that deals with the effects of rising temperatures, the increase in unpredictable and destructive weather and provides some thoughts about what must be done."