THE PHYSICAL PARAMETER IN SEAWATER

NIK NOORHAYATI BINTI NIK ABDUL MAJIDP66094

ADVANCE MARINE CHEMISTRY

OUTLINES

IntroductionThe physical parameter in seawater- Temperature- Salinity- Pressure- pHConclusion

INTRODUCTION

Water exists in all three physical states of matter : solid, liquid and gas

Determine many important oceanographic phenomena, including :

- global pattern of oceanic and atmospheric circulation, the growth and distribution of marine organism

INTRODUCTION

Learning objective

explain variation in temperature, salinity, pressure and pH in the ocean

TEMPERATURE

Very important characteristic of seawater

The temperature of seawater is fixed at the sea surface by heat exchange with the atmosphereThe average incoming energy from the sun at the earth’s surface is about four times higher than at the poles

TEMPERATURE

The main physical mechanism is turbulent mixing water by wind and waveEstablish a mixed surface layer that can be as thick 200-300 m Temperature declines rapidly throughout the water column is call thermoclineIt is measured in (Celsius (˚C), Kelvin (K) and Fahrenheit (F))

TEMPERATURE

• Tropical are permanently layer

(warm, less dense surface water from cold, dense deep

water by thermocline)

• Temperate regions have a seasonal thermocline, and pole regions have

none

TEMPERATURE

Bridge Thermometer

Tank Thermometer

Cargo-Hold Thermometer

Thermometer refill

SALINITY

Seawater is mixed of 96.5% pure water and 3.5% others materials, such as salts, dissolved gases, organic substances and undissolved particlesThe salinity of surface seawater is controlled by the balance between evaporation and precipitation

Unit is part per thousand = ppt = ‰, psu (practical salinity units)

SALINITY

• Salinity map showing areas of high salinity (36‰) in green• Medium salinity in blue (35‰) • Low salinity (34‰) in purple

• North Atlantic, South Atlantic, South Pacific, Indian Ocean and Mediterranean Sea to be a little high (green)

• Areas near Antarctica, Arctic Ocean, Southeast Asia, West Coast of North America tend to be a little low (purple)

http://www.biosbcc.net/ocean/marinesci/02ocean/swcomposition.htm

North Atlantic

South Atlantic

South Pacific

Antarctica

Arctic Ocean

Indian Ocean

Mediterranean Sea

Southeast Asia

SALINITY

(A) Salinometer

(B) YSI Multiparameter

(C) Refractometer - SG (Specifik Gravity) - salinity

Pressure

Pressure is the force per unit area

A function of gravity, density and depth

The SI unit for pressure is the K Pa = 103 Pascal

Ocean pressure is usually reported in decibars where 1 dbar = 104 PaIn the ocean, the downward force of gravity is mostly balance by an upward pressure gradient force, the water is not accelerating downward (hydrostatic balance)

PRESSURE

Pressure increases with the

increasing depth

PRESSURE

Transducer

pH

Measure of dissociation of water into ions (H+, OH)

pH = -log [H+]

pH effects on biological and geochemical reactions

pH

pH = potential/power of hydrogen

pH

pH

YSI Multiparameter pH Meter

CONCLUSION

There are many physical parameter in seawater

Temperature, salinity, pressure and pH the most important parameter in seawaterUnderstand variations in temperature, salinity, pressure and pH and how they alter the chemical and physical properties of the oceanCan make prediction for the future

THANK YOU