North Pacific sea-surface temperature anomalies. Temperature anomalies along P line. Air pressure anomaly at sea surface. The Blob

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1 North Pacific sea-surface temperature anomalies The Blob From Bond et al. 2015, Journal of Geophysical Research Air pressure anomaly at sea surface Temperature anomalies along P line P Line Depth (m) From Bond et al. 2015, Journal of Geophysical Research From Peterson et al. 2015, PICES Press 1

2 Effects of the blob on marine life Cassin s Auklets Warm water species found in North Pacific Skipjack Tuna near mouth of Copper River, Alaska Thresher shark caught in Southeast Alaska Fraser River sockeye salmon migrating north Subtropical plankton off Oregon coast High catches of albacore tuna of WA and OR Mass mortality of Cassin s Auklets Mass mortality of fish and shellfish in Hood Canal Massive triple red tide from California to Alaska! Large numbers of stranded, starving sea lion pups Estimated mortality: 50,000 to 100,000 birds Photo: National Geographic Summer 2015 Beach closures due to multiple harmful algal blooms Mass mortality in Hood Canal Photo: KUOW 2

3 Questions about The Blob How could The Blob be responsible for all these weird occurrences? What caused The Blob? Was it the result of pollution? Climate change? Was it caused by humans? Is it naturally occurring? Did it arrive from outer space? The blob It s complicated Two interacting climate systems in the Pacific: El Nino Southern Oscillation (ENSO) Pacific Decadal Oscillation (PDO) Relatively high air pressure in North Pacific affected the heat budget (reduced cooling of surface water) Reduced upwelling of water offshore led to reduced productivity and created conditions conducive to toxic algal species along the coast Interaction between atmosphere, surface ocean, nutrients, organisms, and (in case of Hood Canal) geologic history Death of The Blob Death of The Blob 3

4 Sea surface temperature anomaly from this summer (July 2016) Sea surface temperature anomaly from this month! High atmospheric pressure offshore Son of Blob! Reasons for return of The Blob Deep water remained warm (deeper than satellite detection range) High atmospheric pressure returned Consequences for marine life? Consequences for winter weather? 4

5 ESCI 321 Introduction to Oceanography Instructor: David Shull Office: ES 445 (4 th floor, down ½ flight of stairs, turn right, door on right) Phone: Web: Just google David Shull 5

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7 ESCI 321 Course web site Canvas Login using universal login ID and password Go to settings and set notifications to something reasonable Primary Fields of Oceanography Geology Weathering Precipitation/ Dissolution Chemistry Sediment erosion deposition Water depth Basin geometry Organic C production & degradation Nutrients Contaminants Physics Circulation pattern stratification Light attenuation Bottom topography Biology 7

8 Satellite image of the Salish Sea Threats to the Salish Sea today from WA Department of Ecology Toxic Chemicals PCB, PAH, heavy metals Polluted Stormwater Primary source of contaminants Chlorophyll concentration in Salish Sea surface waters as determined by satellite Threats? NASA Polluted Tributaries 549 rivers and streams impaired Threatened Wildlife Marine mammals contaminated, threatened Reduced Dissolved Oxygen Hood Canal and elsewhere Loss of Habitat In the past 125 years, about 70% loss Shoreline Development > 30% highly modified Puget Lowland Hypoxia in Hood Canal Water column data from Hood Canal (Twanoh) Tuesday. Twanoh August 2015 (other large fish kills in 2004 and 2006) Other buoys: 8

9 Global distribution of coastal dead zones (> 400) Ocean acidification From Diaz and Rosenberg, Spreading dead zones and consequences for marine ecosystems. Science, 15 August 2008 Reading for next Tuesday Interesting background reading, but not assigned Prologue: The History of Oceanography Oceanography Science begins, Ocean Science in Modern Times Ch. 1: The Water Planet Cosmic Beginnings, Where on earth are you?, Earth is a water planet (Reservoirs and Residence Time) For the second hour of today s lecture, Ch. 2 Ch. 2: Earth Structure and Plate Tectonics (a review?) 2.1 Earth s interior through 2.5 Motion of the Plates For Tuesday, Ch. 3: The seafloor and its sediments 9