THERMOHALINE CIRCULATION - PowerPoint PPT Presentation

1 / 29
About This Presentation
Title:

THERMOHALINE CIRCULATION

Description:

THERMOHALINE CIRCULATION TS Diagrams Global view of thermohaline circulation Circulation at the Straits of Gibraltar Atlantic Ocean thermohaline circulation – PowerPoint PPT presentation

Number of Views:132
Avg rating:3.0/5.0
Slides: 30
Provided by: OCNG252De6
Category:

less

Transcript and Presenter's Notes

Title: THERMOHALINE CIRCULATION


1
THERMOHALINE CIRCULATION
S
  • TS Diagrams
  • Global view of thermohaline circulation
  • Circulation at the Straits of Gibraltar
  • Atlantic Ocean thermohaline circulation
  • Pacific and Atlantic temperature and salinity
    sections
  • The Conveyor Belt

2
Thermohaline circulation
P
  • Below the pycnocline
  • 90 of all ocean water
  • Slow velocity (10-20cm/sec or less)
  • Movement caused by differences in density
    (temperature and salinity)
  • Cooler seawater denser
  • Saltier seawater denser

3
Thermohaline circulation
S
  • Selected deep-water masses
  • Antarctic Bottom Water
  • North Atlantic Deep Water
  • Antarctic Intermediate Water
  • Cold surface seawater sinks at polar regions and
    moves equator ward

4
Thermohaline circulation
P
Fig. 7.25
5
Deep ocean currents
P
  • Cold, oxygen-rich surface water to deep ocean
  • Dissolved O2 important for life and mineral
    processes
  • Changes in thermohaline circulation can cause
    global climate change
  • Example, warmer surface waters less dense, not
    sink, less oxygen deep ocean

6
WATER MASS
  • A defineable volume of water based on its
    temperature-salinity characteristics which come
    from a particular region in the ocean

7
TS Relationships
S
3/18
8
P
9
Thermohaline circulation
S
  • Originates in high latitude surface ocean
  • Once surface water sinks (high density) it
    changes little
  • Deep-water masses identified on T-S diagram

Fig. 7.24
10
S
Water has unique TS characteristics because It
has a common formative origin
11
S
Different geographic areas have different TS
curves - they act as fingerprints because each
water mass has a common formative origin with
unique properties.
12
Global Thermohaline Circulation
S
13
P
14
P
15
The Straits of Gibraltar
S
16
S
17
P
18
Salinity and Temperature
S
19
S
20
S
GYRES
21
P
22
P
Note Mediterranean water
23
P
24
P
25
P
26
P
27
The Global Conveyor Belt
S
28
Thermohaline circulation
S
Fig. 7.26
29
Conveyor-belt circulation
P
  • Combination deep ocean currents and surface
    currents

What goes around, comes around - the time to
complete a cycle (or the residence time in the
deep ocean) is from 750-1,000 years.
Fig. 7.27
Write a Comment
User Comments (0)
About PowerShow.com