OUTGASSING TORRENTIAL RAINS PRODUCED LAKES AND OCEANS DISSOLVED AND UNDISSOLVED ELEMENTS PRESENT VOLUME 1,360,000,000 km 3 VOLUME IS STABLE Water: An Earth History

Water Reservoir Oceans97.24% Ice caps, glaciers2.14% Ground water0.61% Fresh-water lakes0.009% Inland seas0.008% Soil moisture0.005% Atmosphere<0.001% Rivers <0.0001% Source: U.S. Geological Survey

Some fast-moving molecules escape from the liquid

In cool air, H 2 O molecules are more likely to join nuclei

CHANGES DOES NOT CHANGE

MASS / VOLUME g H 2 O / m 3 air

Specific humidity: the mass of water vapour (g) per mass of air (kg) Maximum specific humidity is the maximum mass of water vapour that can be held by 1kg of air at a given temperature

MASS OF WATER VAPOUR TOTAL MASS OF DRY AIR g H 2 O / kg air

The ratio of the amount of water vapour in the air to the maximum amount of water vapour that could be present at the same temperature The relative humidity of saturated air is 100% RH = [H 2 0 vapour content/H 2 0 capacity] x 100

The portion of atmospheric pressure that is made up of water vapour molecules (mb or kPa) SATURATED VAPOUR PRESSURE: The pressure that water vapour molecules would exert if the air were saturated (at a given temperature)

RELATIVE HUMIDITY SPECIFIC HUMIDITY

Sling psychrometer

Why do surfaces facing the wind have more frost?

BLACK FROST

A surface is required for condensation Condensation nuclei >0.1  m best About large nuclei per cm 3 (more in lower troposphere and over land) Source: Dust, volcanoes, factory smoke, forest fires, ocean spray salt, sulphate particles from phytoplankton Hygroscopic or hydrophobic

Fog forms if T d is reached

Cold water advection fog

WHY DOES FOG FORM HERE?

Warm water advection fog

CAN ADVECTION FOG FORM OVER LAND MASSES? YES

Field Station Tambito al Cocal River Base camp 2º30´25´´N, 77º00´02´´W, 1450 m