Sightings from the Treehouse: Elements of Climate Change – Oceans in Motion
“Individually, we are one drop. Together, we are the ocean” (Ryunosuke Satoro, Japanese Poet). Our oceans are under attack in a variety of ways, thus we and future generations are under attack. As we continue this blog series, let’s explore some of those ways resulting from increased temperatures and melting polar ice and permafrost.
Sea Level Rise
Ocean heating, dilution with freshwater from melting glaciers and its corresponding rise in sea levels are occurring at a temperature increase of 1.9 degrees F (1 degree C) – half the IPPC recommended goal of 3.6 degree F (2 degree C). Sea level rise is one of the calamitous impacts of increased Arctic temperatures. The rise is primarily attributed to the melting of land-based glaciers and to a lesser extent, increasing sea temperatures.
It is future sea level rise that will bring the most serious and costly impacts, since today’s rise is incremental. Some US coastal cities are seeing the first signs of rising seas and will require massive infrastructure improvements to stay ahead of salt water intrusion onto streets in Miami, coastal Georgia and into subways in New York City seen during Hurricane Sandy. Listen to Josh Willis, currently NASA’s Oceans Melting Greenland (OMG) Chief Investigator, explain sea level rise in the video below:
NASA estimates a sea level rise of about 1 to 8 feet by 2100 depending on emission reductions, while the Climate Institute currently estimates a sea level rise of about 7 feet by 2100 with no emission reductions. Dr. James Hansen suggests sea level rise could reach multi-meter levels during the next 50 to 150 years from the melting of Greenland’s glaciers occurring at ten times current estimates.
Due to carbon dioxide remaining in the atmosphere, sea level rise will continue over the next couple centuries despite current mitigation efforts. It is expected that sea levels will rise to over 20 feet should Greenland’s glaciers melt, while the loss of Antarctica in the coming centuries could cause levels above 30 feet.
Oceans trap 90 percent of the heat from the atmosphere and are an additional factor in sea level rise due to water expansion from the heat. This is having deleterious effects on marine ecosystems across the planet. According to a MIT study, climate change along with over exploitation of marine fisheries, excess fertilizer runoff, habitat destruction and invasive species have resulted in extensive coastal ecosystem deterioration with 50% of salt marshes, 35% of mangroves, 30% of coral reefs, and 29% of seagrasses already damaged or lost worldwide.
The additional ocean heating also feeds storms by increasing their intensity. Warmer ocean temperatures were implicated in increasing the intensity of Hurricane Sandy in addition to adding to higher tides. Future extreme weather events are expected with increasing ocean temperatures.
Ocean acidification is increasing since the oceans absorb 25 percent of the human produced carbon dioxide in the atmosphere each year. About 560 billion tons of carbon dioxide has been absorbed over the past 250 years increasing acidification by 30 percent, which is 50 times faster than historical rates.
The acidification is already affecting carbonate ions needed by sea life to form coral, shells and zooplankton – the bottom of the food chain. Millions of people depend on the oceans for their livelihood. Research suggests that within 50 years, acidification will limit growth of calcifying organisms. It is unknown how sea life will adapt to such rapid acidification.
Tuvalu, an island nation between Hawaii and Australia, today is facing the real threat of climate change from sea level rise. The Prime Minister, Enele Sopoaga, speaking at the United Nations warned that “Tuvalu’s future at current warming is already bleak,” and “any further temperature increase will spell the total demise of Tuvalu.” These indigenous people did not contribute to climate change, but are one of the first to experience it devastating effects.
The United Church of Christ, active on the island nation, passed a resolution at its General Synod called, “The Earth is the Lord’s – Not Ours To Wreck” calling for environmental imperatives for a new moral era. A new moral era that is grounded in sustaining Creation is needed in all faiths.