Geography and Oceanography - Chapter 19 docx

Using Gliders to Monitor Oregon’s Coastal Ocean OSU Glider Group: Kipp Shearman, Jack Barth, Anatoli Erofeev, Tristan Peery, Justin Brodersen and Laura Rubiano-Gomez •Autonomous Underwa

Using Gliders to Monitor Oregon’s

Coastal Ocean

OSU Glider Group: Kipp Shearman, Jack Barth, Anatoli Erofeev, Tristan Peery,

Justin Brodersen and Laura Rubiano-Gomez

•Autonomous Underwater

Gliders

•Describe the OSU glider

operations

•What are we learning?

•The Future of Ocean Observing

Kipp Shearman College of Oceanic & Atmospheric Sciences

Oregon State University

What’s a glider?

• Autonomous underwater vehicle – a robot!

• Flies by changing its buoyancy

– takes on water, becomes heavy and sinks

– wings turn vertical motion into forward motion

– expels water, becomes light and rises

– flies saw tooth pattern through the ocean

– from the surface to 3 m off bottom (200 m max)

• Slow, but can stay out a long time

– ½ - 1 knot

– 3-4 week endurance

• GPS for positioning

• Communicates to home by Iridium satellite phone

• Collects same data you would on a research vessel at a fraction of

the cost

– Research vessel: approx $20K/day

– Glider: $100K to buy + $200/day (batteries + communications + techs)

Optical Sensors (Chl, CDOM and Backscatter) Pitch Batteries

GPS, Iridium and Freewave Antennae

in tail fin

Webb Slocum Electric Glider

7 ft long

100 lbs in air

The OSU Glider Fleet

Two Webb gliders

Glider Sections

2-5 days per section

100 – 500 m along track resolution

0 to ~3 mab (200 m max) Surface every 6 hrs to get GPS fix, download data and receive new instructions (via Iridium)

21 day endurance Also measures CDOM fluorescence and average currents

Real-Time Glider Data

Students and Gliders

Rice

The Oregonian

Sept 20, 2006

Oregon Field Guide, Episode 1707

Our 15 minutes of fame.

Jane and Bob together for CROOS collaboration

Bob springs a leak

First mission; We fly till Bob runs out of batteries

Bob leaks again

Bob flies through 35+ ft seas!

Jane off New Jersey

Jane drops emergency weight

Bob disappears for 8 days!!

Jane Starts Umpqua River Line, springs leak

Winter – get data when weather allows

Jane surf rescue!

2008 Season: 2-4 gliders

Bob meets UO fansWinter starts early

March 2007

Surf Rescue

Dan and Ollie save Jane from certain doom

Seaglider rescued by Chilean Navy – July 2009

What are we learning?

• The Structure of Upwelling

• Hypoxia on the Oregon shelf

Winds, Ekman Transport and Coastal Upwelling

Northerly winds Offshore Ekman transport

Upwelling brings deep water to the surface near the coast

Deep water cold, nutrient rich and oxygen poor

The Oregonian

July 25, 1996

blue = cold red = warm

Summer vs Winter along the US west coast

courtesy of Andy Thomas (U Maine)

mg/m³

upwelled nutrients feed phytoplankton

Seasonal variations in copepod biomass

at NH 5 (depth = 60 m)

Month of the Year

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

-3 )

0

20

40

60

80

100

1996-1998 1999-2002

May-September Averages + 95% confidence interval

1996 9.2 + 2.54 mg carbon m-3

1997 9.7 + 1.35 "

1998 10.1 + 1.51 "

1999 11.0 + 2.31 "

2000 25.5 + 6.81 "

2001 21.5 + 4.02 "

2002 16.2 + 4.84 "

Phytoplankton feed copepods

Very cold water; 8 °C

Glider Observations of Upwelling

Columbia River Plume

Jane drops emergency weight

Glider Observations of Upwelling

April 5-8

April 19

17-April 19-23

April 27-May 1

May 1-5

May 5-10

Anomalous changes in wind forcing in 2006

Barth/Pierce (OSU)

Twice the amount of upwelling-favorable wind in 2006

Thanks!