Apr 19, 2015

Wedge of warm seawater known as 'the blob' blamed for marine havoc

Washington
USA
by
Monte Morin
,
Los Angeles Times
A storm approaches Williams, Calif., north of Sacramento. Some experts argue that a 500-mile-wide, 300-foot-deep wedge of warm seawater could bring soaking rains to Southern California this winter but also accelerate the rise in global temperatures. Photo: Mark Boster, Los Angeles Times
A storm approaches Williams, Calif., north of Sacramento. Some experts argue that a 500-mile-wide, 300-foot-deep wedge of warm seawater could bring soaking rains to Southern California this winter but also accelerate the rise in global temperatures. Photo: Mark Boster, Los Angeles Times

[S]ome experts have argued that this 500-mile-wide, 300-foot-deep wedge of warm seawater may in fact signal an epic cyclical change in the Pacific Ocean — a change that could possibly bring soaking rains to Southern California this winter but also accelerate the rise in global temperatures.

Though researchers disagree over just what this blob portends, the phenomenon is drawing intense scrutiny from climate scientists and oceanographers.

At the center of this debate is a poorly understood pattern of wind, ocean current and temperature variations that some scientists call the Pacific Decadal Oscillation, or PDO.

Scientists believe that the Pacific Ocean began a cold phase in the late 1990s, and that this was largely responsible for an unexpected slowdown, or so-called pause, in global temperatures. A warm-phase "flip" could reverse that, they say, accelerating the increase in global average temperature and ushering in a period of wetter weather for Southern California and the American South — among other widespread effects