WARMING OCEANS

 

 

 

Human activities are releasing nearly 10 Gegatons of Carbon (about 36 Billion tons of CO2) into the atmosphere every year, driving atmospheric CO2 concentrations to 400 parts per million (ppm) from their original pre-industrial levels of 280 ppm. This increase in CO2 and other greenhouse gases concentrations traps additional energy in the earth's climate system. What happens to this "extra" energy (0.5-1 watt/m2) remains a mystery to many outside the field of climate and sciences.

 

 

Oceans have absorbed 20 times more heat than the atmosphere over the last 50 years resulting in warmer oceans. The recorded increases in ocean temperatures extend well beyond that of natural climate variation. Because of this rise some models suggest that it is likely to warm the air another degree Fahrenheit (0.55° Celsius) worldwide over the coming decades.

 

Sea water 1,500 feet below the surface is warming as well as surface waters. These increases in temperature lie well outside the bounds of natural variation.

 

Where land temperatures are easier to measure that the sea, scientists use several methods to create an ocean record.

 

1. Dropped from ships or airplanes, probes gauging the ocean's conductivity, temperature, and density provide nearly continuous surface-to-bottom measurements at specific times. However, these probes rarely reoccupy an exact location.

 

2. Remote vehicles can measure the temperature of deep ocean waters, and periodically surface to transfer the information to satellites.

 

3. Moorings on the ocean bottom can measure temperatures at fixed distances above the bottom, until a ship retrieves the instruments—typically after a few months or years.

 

4. The most common measurements, however, are taken at the sea surface. Scientists combine these measurements with land surface measurements to calculate the global average temperature.

 

5. Scientists also know that ocean temperatures are rising because warm-water species are moving into areas that were previously too cold, while cool-water and cold-water species are migrating closer to the poles.

 

 

 

PLASTIC - While measuring the temperature of the sea in the arctic, scientists noticed how much plastic was in the water. With acid oceans and climate change, we are really messing things up.

 

 

SOME INCONVENIENT FACTS:

Since 1955, over 90% of the excess heat trapped by greenhouse gases has been stored in the oceans (Figure from IPCC 5th Assessment Report). The remainder of this energy goes into melting sea ice, ice caps, and glaciers, and warming the continent's land mass. Only the smallest fraction of this thermal energy goes into warming the atmosphere. Humans thus, living at the interface of the land, ocean and atmosphere, only feel a sliver of the true warming cost of fossil fuel emissions.

This 90% of extra heat taken up by the ocean is mostly in the upper 700 meters (m) layer (about 60% of total excess heat), while 30% is stored in layers deeper than 700 m (IPCC 5th Assessment Report). The ocean absorbs most of this "anthropogenic heat" because:

Water has a high heat capacity: It takes much more heat to warm 1 liter of water than it does to warm the same volume of air (or most other substances).

 

The ocean is deep: The world's oceans cover 71% of the earth surface and are about 4 km deep on average. This represents a tremendous reservoir of heat.

 

The ocean is dynamic: Heat, carbon, oxygen and various other quantities exchanged with the atmosphere are mixed throughout the ocean through currents, internal waves, eddies, and various other circulation mechanisms.

The largest changes in ocean temperatures were observed in the upper 75 m, due to closer proximity to the atmosphere and the large mixing within this layer (IPCC 5th Assessment Report). As we trap more energy in the earth climate system, heat penetrates further into the ocean. Two important geographic areas where the atmosphere "communicates" with deeper layers of the ocean are the North Atlantic and the Southern Ocean. Because of their distinct atmospheric conditions and geographic settings, surface waters near the poles can be buried into deeper layers, bringing along their heat signatures, thus warming the interior of the ocean.

 

The complex interactions between continued emissions of greenhouse gases, consequent energy imbalance, and changes in the storage and transport properties of heat in the ocean will largely determine the speed and magnitude of longterm anthropogenic climate change impacts. These interactions have significant policy and economic implications, and must not be ignored in the climate policy discussions forum. As the climate negotiators are now shifting their focus towards reaching an agreement on appropriate stabilization targets and designing mitigation and adaptations strategies required to meet those targets, understanding and incorporating the highly important role of ocean as the most powerful climate change mitigator becomes of utmost importance.

 

 

LINKS & REFERENCE

 

http://oceanscientists.org/index.php/topics/ocean-warming

 

 

 

 

HOW MUCH IS THE EARTH HEATING UP - As of early 2017, the Earth had warmed by roughly 2 degrees Fahrenheit (more than 1 degree Celsius) since 1880, when records began at a global scale. The number may sound low, but as an average over the surface of an entire planet, it is actually high, which explains why much of the world’s land ice is starting to melt and the oceans are rising at an accelerating pace. If greenhouse gas emissions continue unchecked, scientists say, the global warming could ultimately exceed 8 degrees Fahrenheit, which would undermine the planet’s capacity to support a large human population.

 

 

ADRIATIC - ARCTIC - ATLANTIC - BALTIC - BAY BENGAL - BAY BISCAY - BERING - BLACK - CARIBBEAN - EAST CHINA SEA

ENGLISH CH - GUANABARA - GULF GUINEA - GULF MEXICO - INDIAN - IRC - MEDITERRANEAN - NORTH SEA - PACIFIC

PERSIAN GULF - SEA JAPAN - STH CHINA - SEA LEVEL RISE - SOUTHERN

 

 

 This website is provided on a free basis as a public information service. copyright © Climate Change Trust 2019. Solar Studios, BN271RF, United Kingdom.

 

 

 

 

OCEANS WARMING UP CLIMATE CHANGE HEAT SINK