Today in the Mission Yearbook - Concern over sea levels is on the rise

Presbyterians for Earth Care turns to NOAA oceanographer to learn about the risks for 30% of the U.S. population

August 19, 2022

Dr. William Sweet

Nearly three in 10 residents of the United States live in coastal counties, according to U.S. Census data — 41 million along the Atlantic Ocean and another 32 million up against the Pacific Ocean.

It’s probably not news to most ocean-adjacent residents that sea levels are rising, owing to a number of contributing factors — not the least of which is climate change. Last week, Presbyterians for Earth Care explored the science behind rising sea levels as well as the likely consequences through a webinar featuring Dr. William Sweet, an oceanographer with the National Oceanic and Atmospheric Administration — who grew up Presbyterian. Watch the 75-minute webinar here.

Sweet, the lead author of February’s 2022 Sea Level Rise Technical Report, said the sea level along the U.S. coastline is projected to rise 10–12 inches over the next 30 years, as much as the rise measured over the last century. By 2050, moderate, or “typically damaging” flooding, is expected to occur on average more than 10 times as often as it does today. Failing to curb emissions could cause an additional 1.5–5 feet of sea rise, or up to 7 feet by the end of the century.

Sweet is part of a team researching and developing products detailing how sea level rise affects coastal flood risk and how people perceive that risk. He helped the U.S. Department of Defense assess coastal flood risk across its global installations, developed the latest sea level rise scenarios for the U.S. and was a lead author for Volumes 1 and 2 of the Fourth National Climate Assessment. He enjoys sailing the Chesapeake Bay and lives in Annapolis, Maryland.

Sweet told webinar participants he grew up in an active PC(USA) church in Raleigh, North Carolina. He recalled “spending time around thoughtful people” who had “voices for good and justice.”

“There are a lot of superlatives, especially with factors concerning ocean levels,” according to Sweet. Carbon dioxide concentration is the highest it’s been in 2 million years. Sea levels are rising at the fastest rate in at least 3,000 years. The retreat of glaciers is unprecedented in at least 2,000 years.

Photo by Karl Fredrickson via Unsplash

Temperatures are rising, and 90% of the excess heat is being absorbed by the oceans.

More frequent extreme rainfall events are projected, especially in the Northeast and Southeast. “Heavy rains will become the new normal,” Sweet said, “and our design systems [including stormwater and wastewater facilities] aren’t meant to handle those.”

The rate of sea level rise is expected to continue as long as emissions cause temperatures to increase, Sweet said. “People need to know what to plan for, whether you’re buying a house or building a seawall.”

One drawback is that even scientists don’t own a crystal ball to help them discern the future. “It’s really conditioned on human actions,” Sweet said. “That’s not a political statement; it’s a scientific statement.”

Projections indicate that sea level rises will be higher along the East Coast and the Gulf Coast than along the West Coast, the Caribbean and the Hawaiian Islands, with northern Alaska somewhere in between.

Some of the effects of sea level rise are already being seen, Sweet noted. A church in Norfolk, Virginia, regularly notes in its online church bulletin which Sundays worshipers will be driving through water to get to church. Scientists have given it a name — nuisance flooding.

“It’s going to grow chronic rather quickly. It’s not a slow, gradual change,” Sweet said of sea level rise. “If you’re getting flooded now, you should expect more of that. If not, be prepared, because it’s going to grow deeper and more widespread.”

Stormwater and wastewater systems within many coastal regions “are now functionally degraded” from routine flooding, Sweet said. “There’s a big cost to upgrade stormwater systems, and it’s looming.”

In addition, “emission matters,” he said. “The thermal memory and momentum of the ocean and long-residence time of carbon dioxide will pose problems for generations.”

“We’re able to say this at NOAA because it’s the science,” he said. What NOAA and other agencies are trying to do, Sweet said, is “put the data in meaningful metrics people can identify with. … It’s there if we open our eyes.”

Mike Ferguson, Editor, Presbyterian News Service

Let us join in prayer for:

PC(USA) Agencies’ Staff
Heather Colletto, Program Administrator, Presbyterian CREDO, Board of Pensions
Annu Collins, Guest Services Support Group, Stony Point Center, Presbyterian Mission Agency

Let us pray

Holy Spirit, by your light you guide this world toward the Father’s love and accompany Creation as it groans in travail. You also dwell in our hearts, and you inspire us to do what is good. Praise be to you! Amen.