Carbon dioxide and other greenhouse gases (GHGs) are responsible for global warming, the long-term worldwide average warming experienced since the industrial revolution. GHGs arise from human use of fossil fuels for energy. Major emitters of GHGs include both industrialized countries and, in recent decades, developing countries as well. Higher global temperatures cause the extremes of hot and cold, and wet and dry, weather of recent years. This blog examines global warming and its effects.
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This blog is expressly directed to readers who do not have strong training or backgrounds in science, with the intent of helping them grasp the underpinnings of this important issue. I'm going to present an ongoing series of posts that will develop various aspects of the science of global warming, its causes and possible methods for minimizing its advance and overcoming at least partially its detrimental effects.
Each post will begin with a capsule summary. It will then proceed with captioned sections to amplify and justify the statements and conclusions of the summary. I'll present images and tables where helpful to develop a point, since "a picture is worth a thousand words".
Friday, September 6, 2013
China Considers Programs to Limit Greenhouse Gas Emissions
world’s use of energy is expanding.Much
of this demand is concentrated in developing countries of the world, especially
China.Their energy needs are furnished primarily by fossil fuels, leading to
high annual rates of emission of the greenhouse gas carbon dioxide, increasing
in China historically by 6.4% per year.Coal is its principal fuel.
Jiang Kejun, a
scientist at China’s Energy Research Institute, is urging its
national energy policymakers to limit CO2 emissions more
aggressively by emphasizing expanded renewable energy sources and energy
efficiency.Mr. Jiang notes that “time
for effective action is very limited.”
The drastic, yet
feasible, measures promoted by Mr. Jiang are resisted by energy and industrial
interests in China, since they adversely affect China’s economic growth rate and threaten the
viability of existing energy investments.In the meantime, China is starting a handful of pilot projects
using a cap-and-trade emissions market to limit emissions.Additionally a carbon tax and direct limits
on emissions are also under consideration.
Since China is a major contributor to increased
greenhouse gas emissions, it is important that it undertake all feasible
policies to limit them.Global warming
from manmade greenhouse gases is indeed a worldwide problem, requiring a global
approach to solve it.The total
accumulated level of atmospheric greenhouse gases must be stabilized by
reducing annual emission rates toward zero.
worldwide demand for energy has been increasing relentlessly throughout the
period of industrialization.Most of
this energy is provided by burning fossil fuels (coal, oil and natural gas)
which results in corresponding increases in the atmospheric content of carbon
dioxide (CO2), a significant and prominent greenhouse gas (GHG).Combustion of fossil fuels is projected to
continue increasing by several percent annually over the coming decades in the
absence of meaningful worldwide efforts to minimize GHG emissions.
emissions rate among industrialized countries of the world has been increasing
very slowly in the last 10 years or so, because of both intrinsic economic
factors and as a result of various reduction policies put in place.Almost all the increase in the worldwide GHG
emissions rate originates from developing countries, especially China, India, Brazil and Russia.This results from the compounded effects of large populations and high
rates of economic expansion as these countries strive to attain middle class
This post focuses
on actual and proposed policy changes in China that are intended to slow its rate of
emitting GHGs.China has the highest population of any country
in the world, and its people are rapidly becoming more prosperous, placing
great pressure on its economy to provide them a middle class life style.These factors are shared across all the
rapidly growing developing countries such as those listed above.
China’s economy has been expanding rapidly in recent
years.For the decade 1999-2009 the annualized
growth rate of China’s economy (measured as real gross domestic
product) was 10.3%.This has slowed in
the most recent years; China expectsits growth rate to be 7.5% in 2013.Such strong growth is necessarily fueled by
corresponding growth rates in its use of energy, most of which comes from
burning fossil fuels.For example, the
graphic below shows that most of China’s electricity has been generated from
fossil fuels (turquoise shading).
energy generated for major input sources of energy.
In 2011, according
to the U. S. Energy Information Administration (EIA), 65% of electric generation and 70% of its total energy use was powered by
coal, the fossil fuel that produces about twice as much CO2 per unit
of electric energy obtained as natural gas, which supplied 3% of its energy.Among renewable sources, 22% of electric
power was obtained from hydropower (brown shading), 6% from wind power and only
0.2% from solar.
China’s domestic production of coal increased 9%
from 2010 to 2011, becoming the world’s largest producer; including imports China alone consumes half the world’s coal
output.According to the Huffington Post, China brings a new coal-fired power plant on line
every 7-10 days.In addition to
electricity generation, coal powers much of China’s industrial production.
By 2020, China seeks to provide 15% of its energy from
renewable sources.Hydropower will
supply most of this, with wind power being next.
China is expected to dramatically increase its
overall energy consumption over 2010-2040, continuing its rapid growth in use
of energy in recent years (see the graphic below).
Annual rates of
energy usage for China, the U. S. and India.Actual use up to 2010; projected usage thereafter.1 quadrillion = 1 million billion.
As China has drastically expanded its energy
consumption in recent years, so too has its annual rate of CO2
emissions correspondingly.In 2010 it emitted
7,885 million metric tons of CO2 (1 metric ton = ~1.1 U. S. (short) ton).This represents the culmination of an average
increase in annual emissions rate of 6.4%.Projecting forward to the period 2010-2040 the EIA believes the emissions
growth rate will fall to 2.1% per year.
It is clear from
this background that any international effort to limit global warming by
reducing GHG emissions must include China, as well as other developing countries
whose emissions rates are increasing.
by China to Lower Its GHG Emissions Rate.The
rapid expansion of fossil fuel-driven electricity generation, automobile use
and heavy industry in China has led in recent years to severe air
pollution in Beijing and other large urban centers.The New York Times reported
on Aug. 31, 2013 that one environmental scientist, Jiang Kejun, working at the
Energy Research Institute, is urging the national energy policymakers to limit
CO2 emissions more aggressively than at present.He is taking advantage of the growing tide of
public concern over urban air pollution, which is causing China’s leaders to support “firmer, faster
measures for cleaner air” that likely include reducing emissions.With this change in public opinion behind
him, Mr. Jiang and his colleagues advocatea program by which China’s annual emissions rate should reach a
maximum by about 2025, and according to which that maximum would be lower than
previously predicted.It advocates more
intensive emphasis on developing renewable energy sources, implementing energy
efficiency technologies, optimizing China’s economic structure, technology
innovation, low-carbon investments, and development and deployment of carbon
capture and storage (CCS, see an earlier postand the Note at the end of this post).
Mr. Jiang, like
most climate scientists, recognizes that “time for effective action is very
limited.”It still remains for Chinese
policymakers to adopt such aggressive measures.The Times report notes instead that other, less drastic, policies are
being implemented or contemplated.A
pilot project is setting up a cap-and-trade emissions marketin Shenzhen.Six more pilots are planned to start by
2015.The affected emissions are only a
miniscule portion of China’s total amount.Other proposals, not yet implemented, include
a tax on carbon dioxide emissions and guiding limits on emission rates.
Growth vs. Emissions
Limits.China’s government has to balance its decades-old
imperative of rapidly expanding its economy with the newer considerations of
constraining emissions from fossil fuels.Expansion has relied on conventional technologies that are fossil
fuel-intensive; such facilities have useful service lifetimes of several decades
and continue to emit GHGs throughout this period.Policies constraining GHG emissions threaten
the investments made in these facilities, since they may have to be extensively
retrofitted or removed from service to accommodate emissions limitations.Even so, over the past decade or so the government
has successfully adopted a policy of increasing China’s economic emissions efficiency, the weight
of CO2 released in producing a unit national gross domestic
product.This measure has been reduced
significantly over this period, by 2-4% per year.Nevertheless, since fossil fuel energy demand
grows annually by an even larger percentage (see above), China’s net CO2 emissions continue to
increase in spite of gains in efficiency.
refers to the increase in the long-term (annual to decadic) worldwide average
temperature above the temperature before the industrial revolution.It is directly related to total
accumulated level of CO2 and other GHGs in the atmosphere, not
to the annual rate of worldwide GHG emissions.CO2 in particular, once emitted,
persists in the atmosphere for a century or even longer.There is no natural mechanism that depletes
atmospheric CO2 in this short a time frame.Therefore even if the countries of the world
agree to lower emission rates, GHGs continue to accumulate, until
the effective rate approaches zero.The long-term average worldwide temperature will continue increasing
throughout this period, and will stabilize at a new, higher temperature when
emissions rates fall toward zero.
Global warming is
just that, a worldwide phenomenon that merits international attention.Countries whose emission rates
continue increasing (see the graphic above) are of special concern; this
includes large sources in developing countries such as China and others.
crisis of urban air pollution in China’s major cities appears to be the trigger
leading China’s leaders to contemplate putting emissions
limits in place.The corresponding
crisis of global warming itself apparently has been insufficient so far to lead
to a similar intensification of effort, in spite of harmful extreme weather
events occurring in China and elsewhere in Asia.Such events are at least made worse by, if not wholly due to, the
adverse effects of global warming.Mr.
Jiang’s programs, if approved for action, should make a major contribution to
reducing China’s GHG emission rate.
As we grapple with the
need to limit GHG emissions in order to stabilize global warming we should
understand that abating emissions may be considered a zero-sum enterprise.When contemplating investing in new energy
facilities either we can continue
building conventional facilities (fossil fuel generating plants; fossil
fuel-powered cars) with need to expand fuel pipelines and transporting fuels,
or we can build renewable energy facilities coupled with new electric
transmission lines (providing the energy for electric-powered modes of
energy contributes to lowering emissions rates, preserves economic
activity and maintains the demand for labor.
It is strongly
recommended to develop renewable energy whenever the choice confronts us.
Carbon capture and
storage is an experimental technology, currently operational yet open to
improvement, that captures CO2 from fixed power facilities,
compresses it and forces it into underground reservoirs intended to retain it
for thousands of years.As such it is
particularly suited for deployment in China, since coal fuels so much of its
currently there are only four pilot scale CCS projects in China, far fewer than elsewhere in the
world.Not all of them are directly
related to capturing and storing CO2 emissions from power
generation.If CCS technology becomes operational, each power
plant would incorporate it and deliver the resulting CO2 into stable
geological storage sites.