Marine Science

Can the Chesapeake Bay (and its Signature Blue Crabs) Recover?

Publication: NBC News   Date: April 26, 2015   View Article

Blue crab season in the Chesapeake Bay is just around the corner. To fill his coffers between now and then, third-generation Virginia waterman J.C. Hudgins is fishing for menhaden, a type of fish used for bait. What he’s seen in recent days comes as good news: clear water to a depth of eight feet.

“Ten years past, you couldn’t do that,” he said. “And so you know the water quality has improved considerably.”

The Chesapeake Bay is a 200-mile long estuary that runs from Havre de Grace, Maryland, to Norfolk, Virginia and is fed with waters streaming in from a 64,000-square-mile watershed that includes portions of six states and the District of Columbia.

Until recently, the bay was choked with nutrients and sediment spilling in from the 17 million people that call the watershed home.

Deep Argo: Probes in Ocean Abyss Explore Mysteries of Global Warming

Publication: NBC News   Date: October 12, 2014   View Article

Nearly a quarter century ago, Greg Johnson was a freshly minted PhD in oceanography puttering north in the South Pacific Ocean. About every 35 miles, the boat he was on stopped and scientists dropped an instrument overboard to measure temperature and salinity at regular intervals all the way to the seafloor.

This process was repeated in a crisscross pattern throughout the world’s oceans over the course of the 1990s. “At the end of it, we had kind of a blurred snapshot of the state of the ocean in that decade all the way from the surface to the bottom from coast to coast,” he explained to NBC News.

The following decade, scientists re-sampled some transects for the sake of comparison. Taken together, the measurements collected during the World Ocean Circulation Experiment are the best — and for most of the oceans only — data available on temperature and salinity 1.4 miles below the surface.

Today, Johnson is spearheading a project to deploy a global array of robotic floats that will probe to a depth of 3.75 miles, allowing scientists to continuously monitor changing temperature and salinity in the entire ocean except for the deepest trenches.

Who’s Driving That Tanker? New Polar Code For Sailing Emerges

Publication: NBC News   Date: August 23, 2014   View Article

A quarter-century after a drunk captain and his fatigued crew ran the Exxon Valdez onto a reef where it spilled 10.8 million gallons of crude oil into Alaska’s Prince William Sound, new rules are taking shape to prevent a similar disaster in the rapidly opening Arctic Ocean.

There, melting sea ice is opening a new frontier for cruise and cargo ships as well as prospectors for oil, gas, and hard rock minerals.

A key goal of the new rules is to ensure people skilled in navigating ice-strewn seas are aboard every vessel in Arctic and Antarctic waters, according to Lawson Brigham, a distinguished professor of geography and Arctic policy at the University of Alaska, Fairbanks, who has participated in the development of the so-called Polar Code for more than 20 years.

Climate Bomb? Methane Vents Bubble on Seafloor off East Coast: Study

Publication: NBC News   Date: August 23, 2014   View Article

Methane appears to be bubbling up from more than 500 vents on the Atlantic Ocean floor off the U.S. East Coast, according to a new study in a finding that could have profound long-term implications for the global climate.

While scientists suspected these so-called seeps existed there, until now they lurked undetected. Their discovery suggests similar seeps exist throughout the world’s oceans.

The seeps come from gas hydrates, an ice-like combination of water and methane that forms naturally with extreme cold and depth in the ocean. Methane is a potent greenhouse gas, and gas hydrates are thought to hold up to 10 times as much carbon as the earth’s atmosphere.

Giant Waves Pose New Risk for Ships in Ice-Diminished Arctic

Publication: NBC News   Date: August 11, 2014   View Article

Monster waves should be added to the list of hazards faced by ship captains as they plot a course through the waters of the Arctic Ocean, according to a new study that reports observations of house-sized swells in seas that until recently were covered in ice year-round.

“Waves always pose a risk to working at sea,” study author Jim Thomson, an oceanographer at the University of Washington in Seattle, said via email to NBC News from off the coast of northern Alaska. “The unique thing about the Arctic is that it is changing so rapidly that we cannot apply past measurements to understand future risk.”

Pacific Northwest’s Salish Sea Eyed as Fossil Fuel Gateway

Publication: National Geographic News   Date: May 9, 2014   View Article

Trains loaded with crude oil from North Dakota’s Bakken shale formation rumble past the outfield bleachers of the Seattle Mariners’ baseball stadium several times a week. From there, the trains head north, their cargo destined for multiple refineries in Washington State.

The traffic is new: Just three years ago, no oil trains were coming to Washington. Bakken crude is filling a void created by dwindling shipments from aging oil fields on Alaska’s North Slope, and the petroleum industry wants to bring in more. But the push to build more rail and shipping capacity in the Pacific Northwest is spurring debate over how that oil flow will affect the region—and where it should ultimately go.

The Next Exxon Valdez? Remote Alaskan Waters, Experts Fear

Publication: NBC News   Date: March 24, 2014   View Article

A quarter-century after 10.8 million gallons of crude oil gushed from the Exxon Valdez and scarred Alaska’s Prince William Sound, oil spill responders fear that another disaster looms in more remote Alaskan waters where ship traffic is on the rise, due in part to the North American energy boom.

The largest concern centers on the Arctic, where oil exploration and development is progressing in fits and starts, and Unimak Pass in the Aleutian Islands, a choke point on a major shipping route between North America and Asia. Both regions are expected to see increased traffic as summer sea ice disappears and producers of North American crude oil and coal look to export fossil fuels to Asia.

© 2008-2010 Collected Writings By John Roach