mapping the mid-atlantic cold pool with gliderpalooza-2013 w. brown, o. schofield, j. kohut, j....

Mapping the Mid-Atlantic Cold Pool

with GliderPalooza-2013

W. Brown, O. Schofield, J. Kohut, J. Wilkin, & W. Boicourt

Cold Pool Context Cold Pool Measurements – Single GliderCold Pool Mapping – Glider Fleet

MTS/IEEE OCEANS’15 Presentation

21 October 2015

Mid Atlantic Bight (MAB) COLD POOL

Ou & Houghton, 1982NOAA/NMFS 1979 Survey Bottom Temperatures

Remnant winter water …isolated by springtime surface warming/freshening => Cold Pool

HISTORICAL EVIDENCE

.. fed by cold water early summer

Mid Atlantic Bight (MAB) COLD POOL

Ou & Houghton, 1982NOAA/NMFS 1979 Survey Bottom Temperatures

Remnant winter water …isolated by springtime surface warming/freshening => Cold Pool

HISTORICAL EVIDENCE

.. fed by cold water early summer

“coldest patch”

Mid Atlantic Bight (MAB) COLD POOL

HISTORICAL EVIDENCE

.. fed by cold water early summer

.. warmed during summer

NOAA/NMFS 1979 Survey Bottom Temperatures Ou & Houghton, 1982

~ 5 km/day

Mid Atlantic Bight (MAB) COLD POOL

HISTORICAL EVIDENCE

.. fed by cold water early summer

.. warmed during summer

NOAA/NMFS 1979 Survey Bottom Temperatures Ou & Houghton, 1982

~ 5 km/day

COLD POOL SCIENCE QUESTIONS

Relative importance of:

early summer along-shelf advection in Cold Pool “coldest patch” formation ?

top-down & cross-frontal mixing processes in the Cold Pool summer warming ?

different erosion processes in the autumn Cold Pool demise ?

ocean and atmospheric factors causing Cold Pool inter-annual variability ?

Measuring the MAB Cold Pool with Slocum Ocean Gliders

Mapping the 2007 Coastal Ocean ….with a ONE-GLIDER “Fleet “

May-Jun 2007

COLD POOL Established Late Spring – cooling !

Mapping the 2007 Coastal Ocean ….with a ONE-GLIDER “Fleet “

May-Jun 2007

COLD POOL Established Late Spring – cooling !

Tmin = 4.78

Mapping the 2007 Coastal Ocean ….with a ONE-GLIDER “Fleet “

May-Jun 2007

COLD POOL Established Late Spring – cooling !

Tmin = 5.32 Tmin = 4.78

Mapping the 2007 Coastal Ocean ….with a ONE-GLIDER “Fleet “

May-Jun 2007

COLD POOL Established Late Spring – cooling !

Tmin = 5.32

Mapping the 2007 Coastal Ocean ….with a ONE-GLIDER “Fleet “

Jul-Aug 2007

COLD POOLSummer - warming

Tmin = 5.60

Mapping the 2007 Coastal Ocean ….with a ONE-GLIDER “Fleet “

Sep – Oct 2007

COLD POOL 2007 Autumn - warming - erosion

Tmin = 7.71Tmin = 8.48

Mapping the 2007 Coastal Ocean ….with a ONE-GLIDER “Fleet “

Sep – Oct 2007

COLD POOL 2007 Autumn - warming - erosion

Tmin = 7.71Tmin = 8.48

Summary Mapping the 2007 Coastal Ocean ….with a ONE-GLIDER “Fleet “

Glider Transect Tmin … a proxy for Cold Pool temperature “

Apr Jun Aug Oct

12

68

4

Summary Mapping the 2007 Coastal Ocean ….with a ONE-GLIDER “Fleet “

Tmin vs. TimeCooling Phase

Apr Jun Aug Oct

12

68

4

cooling

Summary Mapping the 2007 Coastal Ocean ….with a ONE-GLIDER “Fleet “

Apr Jun Aug Oct

12

68

4

warming

Tmin vs. TimeWarming Phase

Glider Fleet Measurements +

Data Assimilation Models

Mapping the 2013 Coastal Ocean ….with a GLIDER “Fleet “

Summary

Ocean Glider Fleet Measurements ? …. a cost-effective technology for REAL-TIME Cold Pool observation

Transect Minimum Temperature & Departures? …. an effective proxy for Cold Pool Water Mass

Cold Pool Mapping Requirements? …. flexible time/space water mass definitions

Timely Maps of the Cold Pool ? .… require glider data –assimilation ocean modeling

Forecasting MAB Cold Pool Disposition? …. within reach

ESPRESSOBottom Temperature

27 May 2013

Wilkin et al., 2013

Cold Pool Array Design: Model Guidance

Mapping the 2013 Coastal Ocean ….with a GLIDER “Fleet “

Glider Transect Tmin

Mapping the Autumn 2013 COLD POOL ….with a glider pair

2nd week September 3rd week

BLUEBLUE

RU-23

Mapping the Autumn 2013 COLD POOL ….with a glider pair

2nd week September 3rd week

BLUEBLUE

RU-23RU-23

Mapping the Autumn 2013 COLD POOL ….with a glider pair

2nd week September 3rd week

BLUEBLUE

RU-23RU-23

with TEMPERATURE DEPARTURES

TD = T – Tmin

TD statistics suggest

TD < 4.3oC (1 σ)

Defining COLD POOL WATER – 2007 Tmin vs Smin Diagram

with TEMPERATURE DEPARTURES

TD = T – Tmin

TD statistics suggest

TD < 4.3oC (1 σ)

Tmin vs Smin Diagram

Defining COLD POOL WATER – 2007

Mapping the mid-September 2013 COLD POOL in the SNEB

Mapping the mid-September 2013 COLD POOL in the SNEB

The inshore edges of the COLD POOL !

Mapping the mid-September 2013 COLD POOL in the SNEB

The inshore edges of the COLD POOL !

The offshore edges of the COLD POOL !

Mapping the mid-September 2013 COLD POOL in the SNEB

Mapping the mid-September 2013 COLD POOL in the SW MAB

The inshore edges of the COLD POOL !

Mapping the mid-September 2013 COLD POOL in the SW MAB

The inshore edges of the COLD POOL !

Mapping the mid-September 2013 COLD POOL in the SW MAB

The offshore edge of the COLD POOL !

Mapping the mid-September 2013 COLD POOL in the SW MAB

offshore flow of the COLD POOL ?

Mapping the mid-September 2013 COLD POOL in the SW MAB

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?

Summary

Ocean Glider Fleet Measurements ? …. a cost-effective technology for REAL-TIME Cold Pool observation

Transect Minimum Temperature & Departures? …. an effective proxy for Cold Pool Water Mass

Cold Pool Mapping Requirements? …. flexible time/space water mass definitions

Timely Maps of the Cold Pool ? .… require glider data –assimilation ocean modeling

Forecasting MAB Cold Pool Disposition? …. within reach

Summary

Ocean Glider Fleet Measurements ? …. a cost-effective technology for REAL-TIME Cold Pool observation

Transect Minimum Temperature & Departures? …. an effective proxy for Cold Pool Water Mass

Cold Pool Mapping Requirements? …. flexible time/space water mass definitions

Timely Maps of the Cold Pool ? .… require glider data –assimilation ocean modeling

Forecasting MAB Cold Pool Disposition? …. within reach

Summary

Ocean Glider Fleet Measurements ? …. a cost-effective technology for REAL-TIME Cold Pool observation

Transect Minimum Temperature & Departures? …. an effective proxy for Cold Pool Water Mass

Cold Pool Mapping Requirements? …. flexible time/space water mass definitions

Timely Maps of the Cold Pool ? .… require glider data –assimilation ocean modeling

Forecasting MAB Cold Pool Disposition? …. within reach

Summary

Ocean Glider Fleet Measurements ? …. a cost-effective technology for REAL-TIME Cold Pool observation

Transect Minimum Temperature & Departures? …. an effective proxy for Cold Pool Water Mass

Cold Pool Mapping Requirements? …. flexible time/space water mass definitions

Timely Maps of the Cold Pool ? .… require glider data –assimilation ocean modeling

Forecasting MAB Cold Pool Disposition? …. within reach

Summary

Ocean Glider Fleet Measurements ? …. a cost-effective technology for REAL-TIME Cold Pool observation

Transect Minimum Temperature & Departures? …. an effective proxy for Cold Pool Water Mass

Cold Pool Mapping Requirements? …. flexible time/space water mass definitions

Timely Maps of the Cold Pool ? .… require glider data –assimilation ocean modeling

Forecasting MAB Cold Pool Disposition? …. within reach