The Open Shelf Sea. 1. The primary source of buoyancy is surface heat flux. c p = specific heat capacity of seawater (= 3900 J kg -1 K -1 ) mean water.

Slides:



Advertisements
Similar presentations
Lake stratification (and chemistry) Water column is all the same temperature Complete circulation of the water column.
Advertisements

0 The vertical structure of the open ocean surface mixed layer 11:628:320 Dynamics of Marine Ecosystems.
Soil temperature and energy balance. Temperature a measure of the average kinetic energy of the molecules of a substance that physical property which.
Useful texts: Mann & Lazier, The Dynamics of Marine Ecosystems, Blackwell Science. Simpson, In: The Sea, vol 10, chapter 5. Simpson, In: The Sea, vol 11,
WP12. Hindcast and scenario studies on coastal-shelf climate and ecosystem variability and change Why? (in addition to the call text) Need to relate “today’s”
Coastal Ocean Dynamics Baltic Sea Research Warnemünde
Light and Temperature. Light photons- packets of electomagnetic energy wavelength: ultraviolet= short; infrared= long ~ 53% of the incident light/radiation.
Problem Description: Networked Aquatic Microbial Observing System (NAMOS) Problem Description: Networked Aquatic Microbial Observing System (NAMOS) Proposed.
Lecture 7-8: Energy balance and temperature (Ch 3) the diurnal cycle in net radiation, temperature and stratification the friction layer local microclimates.
Patterns in Aquatic Ecosystems Shallow vs Deep Fresh vs Salt Swift vs Stagnant Changing vs Constant Ephemeral vs Permanent Limnology vs Oceanography.
Atmospheric Analysis Lecture 3.
The South Atlantic Bight Cape Hatteras Cape Canaveral.
The thermocline occurs deeper in large lakes because wind energy is transmitted to greater depths Wind energy increases with fetch In small lakes convection.
Basic Ecology I Energy Types of Ecosystems Productivity Energy Flow Trophic levels Food webs/chains.
Disko Bay, Greenland - 624,000 cubic miles of ice; 10% of Earth’s fresh water.
Heat Energy Solar and gravitational energy are the fundamental sources of energy for the Earth's climate system. Air-sea exchanges of heat (& freshwater)
Evaporative heat flux (Q e ) 51% of the heat input into the ocean is used for evaporation. Evaporation starts when the air over the ocean is unsaturated.
Anthropogenic ocean warming: A stress on ocean ecosystems David W. Pierce Tim P. Barnett Climate Research Division Scripps Institution of Oceanography.
Open Oceans: Pelagic Ecosystems II
Spatial coherence of interannual variability in water properties on the U.S. northeast shelf David G. Mountain and Maureen H. Taylor Presented by: Yizhen.
Distinct properties of snow
Extra Credit #3 n May 4 (Monday), 7:30pm Byrne Lecture Dr. Eddie Bernard, NOAA “Tsunamis” Austin Auditorium LaSells Stewart center 1-page reaction paper.
Earth Science: 15.1B Ocean Water and Life
Physical effects on plankton and productivity on the Faroe Plateau E. Gaard, B. Hansen, S. K. Eliasen and K. M. H. Larsen Faroese Fisheries Laboratory.
Stratification on the Eastern Bering Sea Shelf, Revisited C. Ladd 1, G. Hunt 2, F. Mueter 3, C. Mordy 2, and P. Stabeno 1 1 Pacific Marine Environmental.
VERTICAL STRUCTURE OF THE OCEAN – from Knauss Chapters 1 and 2 Oceanographers divide the ocean into zones.
1. TYPICAL TEMPERATURE PROFILES (from Pinet, 1998) Thermocline is a range of depths.
The thermodynamic equation for seawater where is the irreversible internal energy fluxes driven by temperature gradient, i.e., diffusion of heat. F S radiative.
IoE The Basics of Satellite Oceanography. 7. Ocean Color and Phytoplankton Growth Lecture 7 Ocean Color and Phytoplankton Growth.
CLASS 16 HEAT BUDGET OF THE EARTH Basic budget Latitude variations Surface temperatures SEA ICE.
ENERGETICS – (pp. 59 – 63, Figures 4.2, 4.3, 4.4 in Knauss) Visible light energy, from the sun, is absorbed by the earth system This occurs in the 0.4.
Introduction The environmental factors such as light, temperature and nutrients interact with each other in the marine environment and play a major role.
Imagery.
USE THESE VALUES. e(T) = e s (T Dew ) PRACTICE WITH STABILITY.
Transport in Aquatic Ecosystems Horizontal Inflows - Advection Turbulence – critical for vertical fluxes.
Chapter 3 cont. (Heat & Temperatures). Heat & Temperature Basics temperature: the energy of molecular movement heat: a measure of the amount of energy.
Mixing From Stresses Wind stresses Bottom stresses Internal stresses Non-stress Instabilities Cooling Double Diffusion Tidal Straining Shear ProductionBuoyancy.
Typical Distributions of Water Characteristics in the Oceans.
9.3- Energy transfer in air and water. Heat transfer Heat transfer = the movement of thermal energy from area of higher temp. to area of lower temp. Heat.
Modelling 2: Introduction to modelling assignment. A basic physical-biological model. Model equations. Model operation. The assignment.
OEAS 604: Introduction to Physical Oceanography Surface heat balance and flux Chapters 2,3 – Knauss Chapter 5 – Talley et al. 1.
Comparative Limnology
Doney, 2006 Nature 444: Behrenfeld et al., 2006 Nature 444: The changing ocean – Labrador Sea Ecosystem perspective.
Potential temperature In situ temperature is not a conservative property in the ocean. Changes in pressure do work on a fluid parcel and changes its internal.
Density structure of the Ocean - Distribution of temperature and salinity in the ocean.
Satellites Storm “Since the early 1960s, virtually all areas of the atmospheric sciences have been revolutionized by the development and application of.
Salinity and Density Differences VERTICAL STRUCTURE, THERMOHALINE CIRCULATION & WATER MASSES.
“the oceanography of lakes” Study of the functional relationships and productivity of freshwater communities, as they are regulated by the dynamics of.
Coastal Oceanography Outline Global coastal ocean Dynamics Western boundary current systems Eastern boundary current systems Polar ocean boundaries Semi-enclosed.
Energy in Earth’s Processes Unit 5. Introduction  Energy is the ability to do work.  Everything in the universe involves the use or transfer of energy.
Atmosphere-ocean interactions Exchange of energy between oceans & atmosphere affects character of each In oceans –Atmospheric processes alter salinity.
Physical and Chemical Oceanography Part 1: Chemistry.
0 The vertical structure of the open ocean surface mixed layer 11:628:320 Dynamics of Marine Ecosystems.
The vertical structure of the open ocean surface mixed layer
Critical and Compensation Depths (refer to handouts from 9/11/17)
Surface Energy Budget, Part I
How does temperature change throughout the ocean?
Puget Sound Oceanography
Class The Oceans PROPERTIES OF SEA WATER Salinity
Yi Xu, Robert Chant, and Oscar Schofiled Coastal Ocean Observation Lab
Ms. Halbohm Marine Biology
Ms. Halbohm Marine Biology
Mark A. Bourassa and Qi Shi
ENSC 312 – Week 9: Climates of simple, non-vegetated surfaces
The vertical structure of the open ocean surface mixed layer
Properties of Water.
LCDR John Hendrickson 17SEP2008
Basics- as they apply to APES
By: Inigo Gabriel Gutierrez
The vertical structure of the open ocean surface mixed layer
Presentation transcript:

The Open Shelf Sea. 1. The primary source of buoyancy is surface heat flux. c p = specific heat capacity of seawater (= 3900 J kg -1 K -1 ) mean water temperature (in degrees Kelvin) Heat stored = J m -2 evaporation h Q v (advection) QbQb QcQc QeQe Longwave radiation conduction Q s (1-A) Solar heat input

Distribution of heat input: Radiation decays exponentially through the water column, i.e.: k=0.1 m -1 In clear water: 55% heat is input into top 1 m 70% is input within 3 m In typical shelf waters: >90% input within 5 m Heat output occurs from the “skin” of the surface. k is an attenuation coefficient, dependent on wavelength of radiation (e.g. see Kirk, Light & photosynthesis in aquatic ecosystems.)

Stronger tidal currents Add tidal stress  The tidal currents mix the thermal structure up from the seabed: Add wind stress  The wind mixes the thermal structure down from the sea surface: Stronger wind mixing

The rate of change of the Potential Energy of a shelf sea water column, driven by surface heat flux, can be derived as: The rate of increase of the Potential Energy of a shelf sea water column, driven by tidal mixing, can be derived as: Heating > tide-mixing  water column stratifies in summer Heating < tide-mixing  water column remains vertically mixed  = 1.6 x °C -1 volume expansion coefficient of seawater Q = rate of heat flux through surface (W m -2 ) c p = specific heat capacity of seawater (3900 J kg -1 °C -1 ) k b = bottom drag coefficient (~0.003)  = efficiency of tidal mixing (~0.003) u o = tidal current amplitude (m s -1 ) h = depth (m) What happens if the two rates are equal?

mixed front stratified

Shelf Sea (or Tidal Mixing) Fronts. These are the transition regions between the permanently mixed and seasonally stratified shelf waters. By running the phys1d program with a range of values for h and/or u you can investigate the effects of tidal mixing on a shelf sea water column.phys1d We can predict this warm cold cool High h/u 3 Low h/u 3 h/u 3 critical Low u and/or high h will result in a water column that stratifies during spring and summer High u and/or low h will result in a water column that remains mixed.

As the existence of shelf sea fronts became recognised, parallel observations of the biology and chemistry of the fronts showed: 1. Fronts separate the low nutrient, stratified surface water from higher nutrient mixed water (Morin et al., J. Mar. Biol. Assoc., 65, ) 2. Fronts are often observed to be regions of high chlorophyll biomass (Pingree et al., Nature, 258, ) 3. Fronts are regions of enhanced primary production (Horne et al., Scientia Marina, 53, ). Enhanced Primary Production at Tidal Mixing Fronts Useful reading: Mann & Lazier, Dynamics of Marine Ecosystems, 2nd ed. (Blackwell Science) pages

Sea surface temperature Sea surface chlorophyll concentration (AVHRR)(SeaWIFS) 10 th July 1999 (Images courtesy of Remote Sensing Group (Plymouth Marine Laboratory))