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Warming spurs new 400km undersea sound channel in Arctic

News, Ocean, Science, shipping, Sonar No Comments »

Beaufort icebreaker cropIn yet another unforeseen consequence of global warming, scientists have begun charting the extent of a new underwater sound channel in the Beaufort Sea north of Alaska. As recently as the 1970’s, the water here was coldest just below the ice, but in recent decades two warmer layers have developed, one in the first 50 meters of water, and the second at around 200 meters deep.  Since sound in water tends toward the coldest layers, it used to be dissipated by the rough bottom side of the ice, but now it’s reflected between the warm layers and travels much farther. Research in 2014 and 2016 documented sound transmission across 400 kilometers (250 miles), four times farther than before the emergence of this channel, dubbed the Beaufort Lens.

The near-surface has been warmed by an increased flow of meltwater from rivers and by larger ice-free areas exposed to the sun; this slightly warmer surface water has long been present in summer, but used to disappear in winter.  Meanwhile, warmer waters entering the Beaufort from the North Pacific through the Bering Strait (and perhaps even from the Atlantic, through northern Canada) have contributed to the growth of the deeper warm layer. As is the case for most ocean noise research, the US Navy is a key funder; they’re interested in how increased noise transmission might “dramatically impact the effectiveness of sonar operations.”

The full extent of the Beaufort Lens sound channel is not yet known; further research is planned in the spring of 2018. The area affected is likely to vary with annual changes in the influx of warmer waters and to expand over time as longer-term climate change progresses. Increased shipping traffic is projected to be a major factor in rising ocean noise levels in the Arctic over the coming decades; oil and gas exploration could add to the din if the offshore oil industry rethinks its abandonment of these waters in recent years. In addition, general background noise in some areas could also increase thanks to longer-range transmission of whale calls, which have always been one of the primary sources of ambient sound in these waters.

Vancouver reduces harbor rates for quiet ships

News, shipping No Comments »

The Port of Vancouver has enacted a new incentive program to encourage tankers and other ships to adopt noise-quieting technologies.  Beginning on January 1, 2017, ships that have achieved any one of three widely recognized noise-reduction criteria will receive a 47% discount on harbor fees. Ships that have adapted wake flow or cavitation noise technologies will receive a smaller 23% discount.

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This is great news, and we encourage other ports to follow in Vancouver’s enlightened footsteps. It is entirely possible to stop the steady increases in global shipping noise, and even to reverse these trends of the past few decades. Twenty years from now, our oceans can be quieter than they are today, and the isolated pockets still free of humanity’s noise footprints could expand, providing new hope for the world’s ocean creatures.

Much ado about not much in Obama’s offshore oil bans

News, Ocean, Seismic Surveys No Comments »

While I was certainly glad to hear that President Obama has declared most of the Chukchi and Beaufort Seas in the Alaskan arctic “indefinitely off limits” to oil and gas development, the roar of approval from the media and environmentally-minded public was louder than the action actually merits. And the Atlantic withdrawals appear next to meaningless. I know we should never look a gift horse in the mouth, but even a quick glance reveals more gum than enamel in this one. Nonetheless, I’ll take an over-enthusiastic celebratory shout over even the fading ghost of the chance of much more enduring and disruptive roars from seismic surveys, crazy-loud engines on stabilized drilling platforms, and decades of crew transport and tanker traffic. It’s not for nothing that diverse group of scientists and activists have been calling on Obama to do just this for the past couple of years.

Still, I’m here to temper the joy. Before looking at the maps that put the modest impact of this move in perspective, there’s a red flag right up top that deserves a bit more clarification. All commenters, enviros and energy companies alike, seem to agree that this withdrawal is more consequential than the November announcement by the Department of Interior that no lease sales would be offered in either the Arctic or Atlantic for the upcoming 2017-2022 leasing period, a decision that’s won’t be finalized until July and could have been vulnerable to reversal by the incoming administration. Obama’s new declaration likely closes the door on such a rapid reconsideration of these upcoming five-year plans. But notice that the magic word in the withdrawals is “indefinitely,” not “permanently.” It seems that the door is left open to reconsideration: the White House statement detailing the withdrawal states that the “indefinitely off limits” designation is “to be reviewed every five years through a climate and marine science-based life-cycle assessment.” (To be fair, the text is somewhat ambiguous as to whether this 5-year review applies to both the US and Canadian actions, or just the latter.)

UPDATE, 1/11/17: The outgoing administration tied up a worrisome loose end this week by denying six pending applications to do exploratory seismic surveys in the Mid- and South-Atlantic planning areas. This is a one-time denial; future re-applications can be considered at any time. New surveys will be necessary to inform any future lease sales in these areas.

So for now, let’s celebrate that at least the first term of a Trump administration has its hands fairly well tied in its ambitions to expand US offshore oil production from its current focus on the Gulf of Mexico and in a 200 mile strip of waters along Alaska’s Arctic coast. Wait, what’s that? Yep, the big withdrawal announcement doesn’t remove any of the areas already being actively developed off Alaska’s northern shores (brown in this map):

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The good news is that there are currently only a handful of producing wells in that brown strip, on three of the five lease areas owned by one company, Hilcorp, just offshore from Deadhorse (they’re the tiny green areas in the next map, below). In fact, out of the peak of 480 lease tracts in the Chukchi and Beaufort Seas that had been acquired by energy companies as of 2008, only 43 leases (including 53 lease blocks) are still even nominally in the planning pipeline; 42 of them are in this area that remains available to future leasing as well. Falling oil prices, disappointing test well production, and both logistical and increased regulatory hurdles have led many of the companies that were once so enthused about moving into these waters to formally abandon their leases.

Here’s a look at where things stood as recently as July 2015, when the Chukchi was still the focus of industry hopes and dreams: Read the rest of this entry »