Garbage saved

Chapter 2 Is climate warming good news? (1)
Global warming: good news?

Climate CO[-] Sensitivity Global Warming Data
The climate may be less sensitive to carbon dioxide than previously thought.

The complexity of climate science is well known, but it is very useful to keep one indicator in mind, and that is "climate sensitivity".This indicator represents the projected amount of warming that would result from doubling the concentration of carbon dioxide in the atmosphere.In a summary of the science behind its projections (published in 2007), the Intergovernmental Panel on Climate Change (IPCC) estimated that under today's conditions, a doubling of carbon dioxide concentrations would cause a warming of around 3°C, plus or minus Around 1.5 degrees.But the summary also claims that the true figure is slightly more likely to be much higher.Some studies also speculate that temperature rises could reach as high as 10°C.

If this speculation is true, disaster is on its way.But a report in the journal Science by Andreas Schmidtner of Oregon State University in the US suggests that is not the case.In Dr Schmittner's analysis, the climate is less sensitive to carbon dioxide than previously feared.

Existing research on climate sensitivity is largely based on data collected by weather stations dating back to around 1850 AD.Dr. Schmidtner took another approach.His data comes from the peak of an ice age (between 3000 and [-] years ago).His team is not the first to use the data to probe climate sensitivity to carbon dioxide.But their reports are the most comprehensive and thorough.Past studies have only considered small parts of the globe.And he compiled enough information to make a conclusive attempt at reconstructing a climate model of the entire planet.

The team's most likely figure for climate sensitivity is 2.3°C, more than half a degree lower than the accepted figure, and there's a 66 percent chance that it lies between 1.7°C and 2.6°C.What's more, the findings point to an upper limit for climate sensitivity at around 3.2°C.

But before you take your SUV out for a celebratory drive, remember that this is just one study, and like all studies of this kind, research has its own flaws.Dr. Schmidtner acknowledged that the computer models used in the study were of average sophistication.This may also be one reason for the narrow range of his team's experimental results.And, although the study's geographic coverage is the largest of its kind, it still has gaps -- notably Australia, Central Asia, South America and the North Pacific.Moreover, some skeptics grumble that such ancient data have been used to construct a different but related branch of climatology, the so-called "hockey stick model" (which argues that temperatures have risen abruptly since the Industrial Revolution).It will be interesting to see whether these skeptics are willing to treat them with equal skepticism when ancient data support their views.

"White + Black" in climate change

Climate Change Air Pollution Global Warming "Black Carbon" Cooling
An idealized fossil fuel power plant has nothing to mention besides generating electricity and producing carbon dioxide, let alone those carbon-burning equipment, from diesel engines to dung-burning fireplaces and kilns, which also emit various gases and All kinds of viscous waste.These usually bring environmental problems to the local area, hurting crops, damaging lungs and shortening life span.Bituminous coal, or "black carbon," also warms the planet.

According to the United Nations Environment Program (UNEP), remedial measures are known to be "timely and multiple" effective in counteracting the effects of pollutants over the next 20 years.These benefits include a projected 2050°C to 0.2°C reduction in temperature by 0.7 compared to otherwise, and saving 70 to 460 million lives as air quality improves.The measures taken for "black carbon" mainly adopt more efficient combustion methods, and the most important thing for the ozone layer is to reduce the emission of methane so as to promote the formation of the ozone layer in the atmosphere.Measures against "black carbon" have saved more lives than ozone layer control, but in terms of climate, they are more difficult to assess.

Veerabhadran Ramanathan of La Jolla, California, and Paul Crutzen, the Dutch climate scientist who first developed the theory of "nuclear winter," wanted to find out what aerosols -- particles small enough to hang in the atmosphere -- do to climate.Their campaign, which brought together about 150 scientists and a host of research aircraft and satellites, found an "Asian brown cloud" spanning thousands of kilometers that was larger than expected and generated by heat, diesel exhaust, and a variety of other things .

In 2001, Dr. Ramanathan took Klaus Tpfer, then chief executive of the United Nations Environment Programme, on a flight along the foothills of the Himalayas when they saw brown clouds covering the mountains.Since then, UNEP has taken an interest in the issue.

Dr Ramanathan realized that the situation would be similar if thinner clouds were present in Africa or elsewhere.This phenomenon, after modification, is expressed as "atmospheric brown cloud".

It's easier to take action on ephemeral forces like "black carbon" and the ozone layer than to track carbon dioxide.Because carbon dioxide is an inevitable by-product of fossil fuels, controlling carbon dioxide is a first-class economic imperative.And because it has lasted for quite a long time, and it has been mixed on this planet, the United States and China are relatively balanced in terms of emissions.This can easily lead to dead-end negotiations.Relatively speaking, short-lived forcings are relatively cheap to make cuts: reliable and real measures for "black carbon" include replacing old locomotives, filtering exhaust gases, and giving people cleaner fuels , to burn in better fireplaces, to stop the widespread burning of crop waste, and to modernize kilns and ovens.

Some effects like "atmospheric brown clouds" tend to be more regional.Some countries need to work together in many different ways - including regional agreements, bilateral assistance, and comparison of best practices.The availability of more venues and instruments should help climate diplomacy move beyond the never-ending "who should do more" debate.

The science is mature, but the role of "black carbon" and other aerosols in changing climate remains varied.Even the most routine can be scary for policymakers, said Durwood Zaelke, chair of the Institute for Regulatory and Sustainable Development and a consultant to the United Nations Environment Programme.But Durwood Zaelke believes the new report makes clear the uncertainties while making a convincing course of action.

The climate forces, for reasons of comparison with each other, are expressed in watts per square meter: the higher the wattage, the higher the temperature.Based on observations that range from 0.4 to 1.2 watts per square meter, Dr Ramanathan puts this value for "black carbon" at about 0.9 watts per square meter.Several climate modelers tend to take values ​​near the bottom of this range; this means that either the models are underestimating the total amount of "black carbon" that has been emitted, or that Ramanathan's values ​​are too high .

Through multiple factors, this effect of "black carbon" may be amplified or weakened. "Black carbon" isn't emitted alone, but along with other things -- including inorganic molecules like various sulfides and nitrides.These can form lighter-colored particles that reflect rather than absorb the sun's light energy.These lighter-colored aerosols can provide sites for water to condense, thereby ensuring the formation of clouds that reflect sunlight.This is why the "black carbon" in the brown cloud acts as a greenhouse gas, but the net effect of the cloud as a whole is one of the reasons why the Earth below the cloud is cooled.

Such a layer of pollutants warms the atmosphere and cools the Earth's surface well beyond the net warming and cooling effects.Assuming the surface cools and the air above it heats up, it becomes less easy for the air on the surface to rise upward; and the resulting reduction in convection will tend to reduce cloud formation and rainfall.

So all this means that no one can say exactly how much action on black carbon will go to avoid rising temperatures.Tami Bond of Illinois State University said that if it weren't for the clouds, many experts would have hoped for cooling on top of steps to reduce "black carbon," which also cut inorganic compounds and other cooling aerosols. .But given the effect on cloud formation and dissipation (a cloud infused with "black carbon" does not last very long), the potential for error in estimating its eventual effect is high. big. Dr Bond is a lead author on an effort to assess and model "black carbon" and quantify its uncertainties, which will soon be published.

"Black carbon" has a particularly harmful effect in frozen regions.But it falls on the snow, which will greatly increase the absorbed sunlight. "Black carbon" is erupting over the rim of this bathtub across India, which represents a threat to glaciers in the highlands of Asia.Studies of Mount Everest's ice cores show a three-fold increase in "black carbon" from 19745 to 2000.The Arctic is warming faster than elsewhere, and faster than models tend to predict.

If the Arctic warms faster than expected, the rest of the world may warm more slowly.One reason for this, widely accepted by scientists but favored by only a few policymakers, is sulfate emissions from coal-fired power stations and the use of some other fossil fuels used by industry.Sulphates respond well to aerosol formation, which also makes natural clouds whiter and longer, providing more of a cooling effect.

No one knows how much greenhouse gases have warmed the climate over the past few epochs, masked by the cooling effects of sulfate and other aerosols.Some scientists say that global warming has been most masked from the 20s to the 70s, roughly the period when desulfurization of smokestack emissions became more stringent in Europe and North America.Year-on-year warming slowed around the year 90 when China burned coal to generate electricity, and its sulfate emissions soared, reversing the global cooling of previous eras .

That sounds like a free solution - except you have to breathe Chinese air.Pollution is the leading cause of thousands of deaths before adulthood each year.A similar situation occurs in the sea and the ocean.After generations of ships increasing sulfate emissions, the IMO has reversed the trend of regulating fuel sulfate content.Analysis by independent scientists reveals that this would save tens of thousands of life forms in coastal areas, but could increase warming by about 0.3 watts per square meter - a significant amount.The act of removing sulphate from the atmosphere, which makes sense on a healthy note, could easily warm the world much more than would offset the cooling from black carbon.

So, how to solve such a difficult problem?Regulators mostly turn a blind eye.Even if one were able to compare the number of lives lost to positive action versus indifference, a Kantian neurotic search for meaning and consequences would presumably prevent one from doing anything about those conclusions.

(End of this chapter)