WATER AND THE CLIMATE

According to Allen Hunt, global climate and its variability cannot “be understood if impacts of water are neglected.” (Hunt). Water plays a very important role in determining climate worldwide. The largest subsection of water formations that contributes to climate change, holding 96.5% of the water on earth, are the oceans. (Hunt)

 

For us Americans, one of the most notable effects of climate change in the short term will be the rising of the sea due to melting glaciers. Coastal regions will be negatively impacted by this phenomenon. (NOAA) However, the rising of the ocean is not the most interesting aspect of water when it comes to climate change.

 

The reason that the ocean is such an important player in climate change is that it is wet. (NOAA). While this seems a simple assertion, it is often not appreciated fully. (NOAA). Because of its phase, liquid water has a very high heat capacity, and an even higher on in its vapor form (NOAA). More evaporation of the ocean occurs as the world heats due to the release of greenhouse gasses. This can be manifest in El Nino events in the Pacific, caused by rising surface ocean temperatures which usually occur on the 3-7 year range of cycle. (NOAA). El Nino events have been occurring with increasing rapidity since the phenomenon of global warming has become a factor in the state of the global environment.

 

The atmosphere doesn’t have as much heat potential as water. And while we live on land, neither is it a good conductor of heat. (NOAA) It is therefore, we can logically deduce, the qualities of water related to its ability to conduct heat that determines the temperature, and therefore the climate, of a certain region. (NOAA)

 

As the world has gotten warmer, the past 150 years have seen a rise in ocean temperature. However, this rise is not instantaneous. Heat from the vaporous atmosphere penetrates into the ocean “through a combination of radiation, convective overturning (in which cooled surface waters sink while warmer more buoyant waters below rise) and mechanical stirring by winds.” (NOAA) It can take, when convective overturning occurs, up to 100 years for the surface temperature of the ocean to mirror instantaneous warming precipitating from global warming today. Heat is pulled to the equator, where it is input into the ocean. (NOAA) It then moves to the poles, where heat loss into the atmosphere occurs, causing the melting of polar ice and general heating of the globe. (NOAA) We have seen global temperatures rise at a rate of unprecedented proportions in the past centuries.

 

The ocean’s waters are the primary way that heat is transferred to land, and surface temperatures that have been warmed by today’s global warming will only start to affect land temperature in 100 years. We’ve already seen a lot of warming, but this will only increase, to a very scary degree, in the coming centuries when the latent heating of ocean water manifests itself on human-inhabited land.

 

According to Benjamin Santer of the Lawrence Livermore National Laboratory's Program for Climate Modeling and Intercomparison, “When you heat the planet you increase the ability of the atmosphere to hold moisture. The atmosphere’s water vapor content has increased...and natural variability in climate can’t explain this moisture change. The most plausible explanation is that it’s due to the human-caused increase in greenhouse gasses.” (Hunt) More vapor doesn’t just mean more precipitation. It also will, in the coming decades, mean more heat in the atmosphere, and will continue to exacerbate the global warming we’ve witnessed.

 

The updated Koppen-Geiger system of climatic classification will need to be updated even more as the decades wear on. The scale will continue to be tipped in the favor of the red end of the spectrum, as warming is expounded by rising ocean temperatures.

 

 

 

Global Water Systems Lecture, Allen Hunt

 

The Role of Oceans in Climate, NOAA Ocean Climate Observation Program

 

 

NOTES on WORLD WATER CYCLES from ALLEN HUNT's LECTURE

JUNE 17 WORLD WATER CYCLES

hydrology-how water moves

Earth’s carrying capacity: surpassed in 1970s

water has a lot to do with carrying capacity

 

WATER

94% SALINE

2.5% FRESHWATER

 

1% OF FRESHWATER IS SURFACE

OF SURFACE WATER:

70% ICE

20% LAKES

2% SWAMPS

0.5% RIVERS

VULCANIST WATER CYCLE: CARBON STORAGE

 

STORAGE//FLUX (DYNAMICS OF WATER)

EG HOW MUCH WATER FLOWS INTO OCEAN FROM RIVERS AND VICEVERSA

EG HOW FAST IS WATER FLOWING?

SMALL VELOCITIES = LARGE STORAGE

LARGE SOURCES OF WATER NOT REPLACED READILY

 

IMPERMEABLE SURFACES INCREASE FLUX (RUNOFF), DETRIMENT STORAGE

 

HYDROLOGIC PROCESSES GRAPH

 

PLENTY OF GROUNDWATER FLOWS MAKE IT TO THE OCEAN

PARTICLES (SALTS) ARE INTRODUCED TO OCEAN VIA FLOWS

THEREAFTER, SALT IS EMBEDDED IN ROCK

WATER AND TECTONICS

WATER HAS DIFFERENT PERMUTATIONS

SOME MOLECULES CONTAIN OXYGEN 18, SOME 16

(NUCLEAR LEVEL, DIFFERENT)

(CHEMICAL COMPOSITION, SAME)

EVAPORATED WATER CARRIES CHEM SIGNALS

WATER CONDUCTS AND TRANSPORTS HEAT

 

2 CYCLES

TECTONIC

SOLAR

 

ADDITIONAL ROLES OF WATER IN HYDROLOGIC CYCLE

MOST IMPORTANT GREENHOUSE GAS

LATENT HEAT TRANSFER

ABSORBS SOLAR RADIATION

 

CLIMATIC ZONES ARE DIFFERENTIATED BY WATER (AND ITS HEAT TRANSPORT POTENTIAL)

 

GLOBAL WATER DISTRIBUTION:

IN ORDER TO UNDERSTAND:

WATER AND CLIMATE

NEOTECTONICS

 

 

MOST WATER VAPOR EXISTS AROUND EQUATOR

PACIFIC, SPECIFICALLY, HAS MOST

MAP OF WATER VAPOR DIRECTLY CORRELATES TO SEA TEMPERATURE

 

 

OCEAN CURRENTS AFFECT HEAT DIST (ALSO DUE TO TOPOGRAPHY)

WEST HEMISPHERE IS WARMER

CALIFORNIA IS DRY, EAST COAST WET

CORIOLIS EFFECT (CURLING OF HOT WATER)

OCEAN WATER TEMP DETERMINES WHETHER JUNGLE OR DESERT FORMS

WHAT CAUSES SEASONS? TILT OF EARTH

WATER ON EQUATORIAL LAND EVAPORATES

WATER VAPOR RISES ON EQUATOR

PULLS UP WATER OF FROM OCEAN

COOLS OCEAN IN THAT AREA

WATER HEATS AS IT SINKS--HADLEY CYCLE

 

SAHARA IS A REFRIGERATOR

AT EQUATOR, 1000 MI/HR

AT POLES, SLOWER SPEED

DEFLECTED TO EAST WHEN TRAVELING TO POLES

DEFLECTED TO EAST WHEN TRAVELING TO EQUATOR FROM POLES

TIBETAN MOUNTAIN (HIMALAYAS) CREATES INDIAN TROPIC (MONSOON)

EROSION IN INDIA (SEDIMENT CARRIED BC OF MONSOONS)

FOG VS RAIN

 

 

heating at equator and hadley cells (1st half)

cooling at poles (2nd half)

jet stream

waves

failure of jet stream