Is Your Global Warming?
Author: J Schipper
Author: J Schipper
Carbon dioxide, the greenhouse gas linked to global warming, is
accumulating in the Earth's atmosphere at an increasing rate,
according to a new study released by the US government's
National Oceanic and Atmospheric Administration. The research
has renewed concern that the ability of the environment to
absorb the gas may be waning. The NOAA study said the average
atmospheric concentration of carbon dioxide in 2005 reached 381
parts per million, up from 2.6 ppm since 2004. The annual rate
of increase, which has been recorded since the 1950s, now
exceeds 2 ppm for three of the past four years. This is an
unprecedented increase; 50 years ago, the annual increase was
less than 1 ppm.
The extra CO2 is produced by the burning of fossil fuels,
currently emitting approximately 7 billion tons of carbon per
year, and roughly half is absorbed by vegetation and the
oceans. Researchers believe the yearly fluctuations in CO2
build-up are caused largely by nature's variable ability to
absorb the emissions. The atmospheric concentration of carbon
dioxide is now higher than experienced on Earth for at least
the last 400,000 years, and the rise is expected to continue.
Over the past two decades, only half of the CO2 released by
human activities such as fossil fuel burning, the so-called
"anthropogenic CO2," is still in the atmosphere; about 30% has
been taken up by the ocean, and 20% by the terrestrial
biosphere.
This new finding follows reports that 2005 was probably the
warmest year on record, with temperatures slightly higher than
the previous peak in 1998. Also, scientists at the US National
Snow and Ice Data Center, in Boulder, Colorado, reported that
Arctic sea ice did not reform fully in the winter of 2005 after
record rates of melting during the summer.
Until recently the largest increases in concentrations of CO2
always occurred during El Niño years, when tropical vegetation
grows more slowly due to lack of rain and fires occur in
dried-out rainforests. The greatest recorded increase of 2.7
ppm occurred in the El Niño year of 1998. However, scientists
are alarmed by the fact that none of the past three years of
near-record increases have coincided with an El Niño event.
According to Peter Cox, a scientist at the Center for Ecology
and Hydrology in Dorset, UK, who studies the interaction
between plants and the atmosphere, the recent surge in CO2
levels "may be the first evidence of a feedback from the carbon
cycle, in which plants under heat stress from global warming
start to absorb less carbon dioxide".
Not only are plants slowing their rate of CO2 absorption, but
coastal carbon sinks are shrinking as well. Mangrove forests,
which play a large role in sequestering carbon from the
atmosphere and dissolving it into the ocean, are disappearing
rapidly. A research team led by Thorsten Dittmar of Florida
State University in Tallahassee studied how much mangroves
contribute to the organic carbon dissolved in ocean waters off
the coast of Brazil. They came to the conclusion that even
though intertidal mangrove forests cover only 0.1% of the
earth's surface, they contribute up to 10 per cent worldwide of
the ocean's dissolved organic carbon. This is approximately
equal to the amount reaching the ocean from the Amazon river,
the largest single source of dissolved organic carbon.
Intertidal forests of mangroves surround many tropical
coastlines. Mangroves, like all plants, fix carbon dioxide from
the atmosphere through photosynthesis and return organic
material to the soil when they decompose. Their tangled root
systems also collect fallen leaf litter. However, mangrove
roots and soil are washed over by tides, and much of this
organic carbon leaches into the ocean. Unlike CO2 absorbed
directly from the atmosphere, much of the carbon produced by
mangrove trees is bound up in large molecules which are highly
resistant to decomposition, and is therefor likely to be held
in the ocean for decades instead of being returned to the
atmosphere as carbon dioxide.
Mangrove forests have declined by nearly fifty percent during
the past century due to increasing coastal development and
habitat damage, such as the draining of swamps for agriculture.
As the habitat has changed, fewer mangrove trees and their
derived detritus are available to bind and export dissolved
organic matter into the ocean. The research team concluded that
the rapid decline in mangrove forests threatens to shut off this
important link in the carbon cycle, with potentially damaging
consequences for atmospheric composition and climate.
Direct absorption of CO2 by the ocean surface also occurs, but
it has unfortunate consequences not produced by complex carbon
molecules fixed by plants. As dissolved CO2 rises, the pH of
the ocean water decreases, becoming more acidic. This low pH
causes the calcium carbonate shells of sea creatures to
dissolve or form poorly, threatening coral reefs.
A pH reduction of approximately 0.1 unit in surface waters has
occurred already due to oceanic uptake of anthropogenic CO2.
Scientists estimate that the total drop in surface seawater
acidity (pH) will be approximately 0.4 pH units by the end of
this century, with an almost 50% increase in the concentration
of dissolved carbonate ion concentration. The surface ocean pH
drop would be lower than it has been for more than twenty
million years.
About The Author: J Schipper is interested in Global Warming
http://www.global-warming-now.info
http://www.stem-cells-now.info http://www.911-faq.info
http://www.life-extension-now.com
accumulating in the Earth's atmosphere at an increasing rate,
according to a new study released by the US government's
National Oceanic and Atmospheric Administration. The research
has renewed concern that the ability of the environment to
absorb the gas may be waning. The NOAA study said the average
atmospheric concentration of carbon dioxide in 2005 reached 381
parts per million, up from 2.6 ppm since 2004. The annual rate
of increase, which has been recorded since the 1950s, now
exceeds 2 ppm for three of the past four years. This is an
unprecedented increase; 50 years ago, the annual increase was
less than 1 ppm.
The extra CO2 is produced by the burning of fossil fuels,
currently emitting approximately 7 billion tons of carbon per
year, and roughly half is absorbed by vegetation and the
oceans. Researchers believe the yearly fluctuations in CO2
build-up are caused largely by nature's variable ability to
absorb the emissions. The atmospheric concentration of carbon
dioxide is now higher than experienced on Earth for at least
the last 400,000 years, and the rise is expected to continue.
Over the past two decades, only half of the CO2 released by
human activities such as fossil fuel burning, the so-called
"anthropogenic CO2," is still in the atmosphere; about 30% has
been taken up by the ocean, and 20% by the terrestrial
biosphere.
This new finding follows reports that 2005 was probably the
warmest year on record, with temperatures slightly higher than
the previous peak in 1998. Also, scientists at the US National
Snow and Ice Data Center, in Boulder, Colorado, reported that
Arctic sea ice did not reform fully in the winter of 2005 after
record rates of melting during the summer.
Until recently the largest increases in concentrations of CO2
always occurred during El Niño years, when tropical vegetation
grows more slowly due to lack of rain and fires occur in
dried-out rainforests. The greatest recorded increase of 2.7
ppm occurred in the El Niño year of 1998. However, scientists
are alarmed by the fact that none of the past three years of
near-record increases have coincided with an El Niño event.
According to Peter Cox, a scientist at the Center for Ecology
and Hydrology in Dorset, UK, who studies the interaction
between plants and the atmosphere, the recent surge in CO2
levels "may be the first evidence of a feedback from the carbon
cycle, in which plants under heat stress from global warming
start to absorb less carbon dioxide".
Not only are plants slowing their rate of CO2 absorption, but
coastal carbon sinks are shrinking as well. Mangrove forests,
which play a large role in sequestering carbon from the
atmosphere and dissolving it into the ocean, are disappearing
rapidly. A research team led by Thorsten Dittmar of Florida
State University in Tallahassee studied how much mangroves
contribute to the organic carbon dissolved in ocean waters off
the coast of Brazil. They came to the conclusion that even
though intertidal mangrove forests cover only 0.1% of the
earth's surface, they contribute up to 10 per cent worldwide of
the ocean's dissolved organic carbon. This is approximately
equal to the amount reaching the ocean from the Amazon river,
the largest single source of dissolved organic carbon.
Intertidal forests of mangroves surround many tropical
coastlines. Mangroves, like all plants, fix carbon dioxide from
the atmosphere through photosynthesis and return organic
material to the soil when they decompose. Their tangled root
systems also collect fallen leaf litter. However, mangrove
roots and soil are washed over by tides, and much of this
organic carbon leaches into the ocean. Unlike CO2 absorbed
directly from the atmosphere, much of the carbon produced by
mangrove trees is bound up in large molecules which are highly
resistant to decomposition, and is therefor likely to be held
in the ocean for decades instead of being returned to the
atmosphere as carbon dioxide.
Mangrove forests have declined by nearly fifty percent during
the past century due to increasing coastal development and
habitat damage, such as the draining of swamps for agriculture.
As the habitat has changed, fewer mangrove trees and their
derived detritus are available to bind and export dissolved
organic matter into the ocean. The research team concluded that
the rapid decline in mangrove forests threatens to shut off this
important link in the carbon cycle, with potentially damaging
consequences for atmospheric composition and climate.
Direct absorption of CO2 by the ocean surface also occurs, but
it has unfortunate consequences not produced by complex carbon
molecules fixed by plants. As dissolved CO2 rises, the pH of
the ocean water decreases, becoming more acidic. This low pH
causes the calcium carbonate shells of sea creatures to
dissolve or form poorly, threatening coral reefs.
A pH reduction of approximately 0.1 unit in surface waters has
occurred already due to oceanic uptake of anthropogenic CO2.
Scientists estimate that the total drop in surface seawater
acidity (pH) will be approximately 0.4 pH units by the end of
this century, with an almost 50% increase in the concentration
of dissolved carbonate ion concentration. The surface ocean pH
drop would be lower than it has been for more than twenty
million years.
About The Author: J Schipper is interested in Global Warming
http://www.global-warming-now.info
http://www.stem-cells-now.info http://www.911-faq.info
http://www.life-extension-now.com
