Atlantic Ocean Maury Project 2013 CAPT Bill Schulz US Naval Academy [email protected].

Atlantic Ocean

Maury Project 2013CAPT Bill Schulz

US Naval Academy

[email protected]

Atlantic Ocean Facts• The most studied ocean• Second-largest of the world’s oceans• Born: about 170,000,000 B.C. • Area: ~77 million km2 (~ 6.5 times the area of

U.S.)• Average depth: 3575 meters (11,072 ft)• Volume: 337,000,000 km3 ( 8.9x1019gallons)• Average surface salinity: 35.37 ppt

– Higher than Pacific due to greater evaporation• Still growing

Atlantic Ocean Basin

• Atlantic is in Stage III of Ocean Basin Evolution:

• A MATURE basin• Spreading ~3 cm/year

• USGS - Understanding Plate Motions

Mid-Atlantic Ridge

Stage III

Maury Project: Atlantic Ocean Brief

I – embryonic (crustal extension, rift; East Africa)II – young (subsidence, spreading; Red Sea)III – mature (spreading; Atlantic)IV – declining (spreading and shrinking; Pacific)V – terminal (shrinking, uplift; Mediterranean)VI – relict scar (Indus Suture)

Stages of Ocean Basin Evolution

Maury Project: Atlantic Ocean Brief

Age of Oceanic Crust – Millions of Years Before Present

• Large ridge/rise system - ~ 70,000 km long

• Not nearly as seismically active as the Pacific

• Youngest crust down the center, rising and forming the Mid-Atlantic Ridge

Atlantic Ocean Basin

Major Surface Currents in the

Atlantic

UCAR's Windows to the UniverseOcean currents tutorial from RSMASTomczak & Godfrey Regional Oceanography text

Wind Drives Atlantic Ocean Circulation

1 Sv = 264 million g/sec

WesternBoundaryCurrent

EasternBoundaryCurrent

Motion due to the wind (and Coriolis) affects the vertical structure of the water column (and therefore, temperature, biology, sound, etc….)

Maury Project: Atlantic Ocean Brief

Atlantic Thermohaline Circulation

• General Concept (National Climatic Data Center) – Sun’s heat absorbed in tropical ocean carried to the North Atlantic

• Oceanic conveyor belt - the large-scale 3-D flow pattern that results from the sinking of water in the Nordic and Greenland Seas and around Antarctica.

Maury Project: Atlantic Ocean Brief

Modified from figure courtesy of Dr. Steve Hovan, Indiana University of

Pennsylvania.

Density Distribution

AABW – Antarctic Bottom WaterAAIW – Antarctic Intermediate WaterNADW – North Atlantic Deep WaterUPPER – North Central Atlantic Water

Tem

pera

ture

(o C

)

Salinity (PSU)

Maury Project: Atlantic Ocean Brief

Atlantic Meridional Overturning Circulation

www.theresilientearth.com

• Salt (Mediterranean Sea)

• Fresh Water (Amazon and Congo Rivers)

• Sediment (St. Lawrence, Niger, Rhine Rivers)

• Heat (Caribbean Sea and Gulf of Mexico)

• Bottom Water (Arctic and Antarctic Seas)

ATLANTIC WATER MASS INPUT:

Maury Project: Atlantic Ocean Brief

Mediterranean Outflow• Large evaporation in the Med.• Produces dense/salty water, which then

sinks. (Levantine Intermediate Water + Mediterranean Deep Water )

• Water spills over the sill at Gibraltar, As the plume of MOW exits Gibraltar, it moves to the north, then spreads west and south

• MOW mixes with and settles with the North Atlantic Deep water, and spreads out one thousand km across the basin.

Temperature at 1000 m depth (from Tomczak and Godfrey)

Maury Project: Atlantic Ocean Brief

The Gulf Stream

• Current on the western boundary of the Atlantic Ocean

• Western boundary currents are much narrower and faster than eastern boundary currents

• Western boundary currents move significant amounts of warm waters northward and are important in transporting excess heat from the tropics towards the poles.

• Eddies form along the meandering Gulf Stream

Gulf Stream

Maury Project: Atlantic Ocean Brief

“There is a river in the ocean. In the severest droughts it never fails, and in the mightiest floods it never overflows; its banks and its bottom are of cold water, while its current is of warm; the Gulf of Mexico is its fountain, and its mouth is the Arctic Sea. It is the Gulf Stream. There is in the world no other such majestic flow of waters.” - Matthew Fontaine Maury 1855

NOAA AVHRR 1996

U.S. Coast and Geodetic Survey

1860Franklin-Folger 1770

Views of the Gulf Stream

Maury Project: Atlantic Ocean Brief

Naval Research Lab Gulf of Mexico Currents(Global NRL Layered Ocean Model – NLOM)

20 April 2010Deep Water Horizon

NOAA Oil Spill Map

The Loop Current

Maury Project: Atlantic Ocean Brief

Air-Ocean Interaction and The Atlantic Ocean

• Hurricanes– 2013 expected to be slightly above average (Gray,

Colorado State, 2013)– 18 named storms (avg=12), 9 hurricanes (avg=6.5

avg), 4 major (avg = 2)

• Atlantic role in Extra-Tropical Cyclones

Maury Project: Atlantic Ocean Brief

Atlantic Hurricanes

• Warm ocean water (> 78.8 F;26 C) is a main ingredient for formation of Hurricanes– NASA Earth Observatory - Hurricane Tutorial

• Climatology– National Hurricane Center

• Storm surge (wind piling up water) is biggest damager COMET storm surge tutorial

• Satellite Imagery– Of Past Hurricanes Archive Imagery from CIMSS– Of Current Ocean Basins NRL Satellite Homepage

, NRL Tropical Cyclone Page

Maury Project: Atlantic Ocean Brief

Maury Project: Atlantic Ocean Brief

The Historic 2005 Season- 27 Named Systems- 15 Hurricanes

Saffir Simpson Scale

Type Category Pressure (mb)

Winds (knots)

Winds (mph)

Surge (ft)

Depression TD --- < 34 < 39 ---Tropical Storm

TS --- 34-63 39-73 ---

Hurricane 1 > 980 64-82 74-95 4-5Hurricane 2 965-980 83-95 96-110 6-8Hurricane 3 945-965 96-112 111-130 9-12Hurricane 4 920-945 113-135 131-155 13-18Hurricane 5 < 920 > 135 > 155 > 18

Maury Project: Atlantic Ocean Brief

Hurricane IsabelSep 2003

• Extensive flood damage along Chesapeake Bay coastline due to storm surge

• USNA Flooded

Maury Project: Atlantic Ocean BriefBiloxi, MS 2 Sept 2005

Biloxi, MS 13 Nov 2001

Powerful storm surge and winds from Hurricane Katrina (Aug 2005) rip two floating casinos in Biloxi, MS from their moorings, relocating them across a highway.

Other significant damage to structures, landscape and vegetation are also observed.

Casino 1

Casino 1 Casino 2

Casino 2

From: Spaceimaging.com

Maury Project: Atlantic Ocean Brief

Radar Imagery of Landfall of Hurricane Dennis (July 2005)

NWS National and Regional Radar Composites

Maury Project: Atlantic Ocean Brief

Impact of ENSO on ATL Hurricane Season?

• El Niño (warm equatorial Pacific) leads to fewer ATLANTIC cyclones

• La Niña (cooler equatorial Pacific)favors ATLANTIC cyclone development

• Currently (26 June 2012) largely neutral, 50% chance of El Niño conditions developing in later half of 2012.

• ENSO module later in the Project, in the meantime:– Climate Prediction Center - ENSO Discussion– NWS JetStream - Weather Impacts of ENSO

Maury Project: Atlantic Ocean Brief

Additional On-Line Education Resources

• Oceans activities from Education World – Celebrate the Year of the Ocean– A "Sea" of Resources on the Internet!

• Tutorials on Hurricanes– WW2010 Tutorial - Hurricanes– NASA Earth Science for Kids - "Tropical Twisters"– Community Learning Network (CLN) - Hurricane learn

ing and activity resources list

Maury Project: Atlantic Ocean Brief

On-Line Education Resources, Cont’d

• Consortium on Oceanographic Activities for Students and Teachers (COAST) - Resource Guide

• JPL - Resources for OC / MET and Remote Sensing of the OCN/ATM

• Smithsonian Museum of Natural History – Ocean Exhibits– Smithsonian Ocean Planet - outdated– Smithsonian - Sant Ocean Hall

• List of Oceanography resources from NCSU• NWS Tutorial - Thunderstorm Tornado Development