Air pollution is a growing problem in most cities (big and small). The "Daily Dose" aims to disseminate the best available information on air pollution and engage in discussions to better understand the process of air quality management. For more details on the program, please visit http://www.urbanemissions.info
Arctic sea icecap disappears, leaving polar bears homeless and changing the Earth's energy balance dramatically as reflective ice is replaced during summer months by darker sea surface. Now expected by 2030 or even earlier.
Tropical coral reefs suffer severe and repeated bleaching episodes due to hotter ocean waters, killing off most coral and delivering a hammer blow to marine biodiversity.
Droughts spread through the sub-tropics, accompanied by heatwaves and intense wildfires. Worst-hit are the Mediterranean, the south-west United States, southern Africa and Australia.
2C-3C
Summer heatwaves such as that in Europe in 2003, which killed 30,000 people, become annual events. Extreme heat sees temperatures reaching the low 40s Celsius in southern England.
Amazon rainforest crosses a "tipping point" where extreme heat and lower rainfall makes the forest unviable - much of it burns and is replaced by desert and savannah.
Dissolved CO2 turns the oceans increasingly acidic, destroying remaining coral reefs and wiping out many species of plankton which are the basis of the marine food chain. Several metres of sea level rise is now inevitable as the Greenland ice sheet disappears.
3C-4C
Glacier and snow-melt in the world's mountain chains depletes freshwater flows to downstream cities and agricultural land. Most affected are California, Peru, Pakistan and China. Global food production is under threat as key breadbaskets in Europe, Asia and the United States suffer drought, and heatwaves outstrip the tolerance of crops.
The Gulf Stream current declines significantly. Cooling in Europe is unlikely due to global warming, but oceanic changes alter weather patterns and lead to higher than average sea level rise in the eastern US and UK.
4C-5C
Another tipping point sees massive amounts of methane - a potent greenhouse gas - released by melting Siberian permafrost, further boosting global warming. Much human habitation in southern Europe, north Africa, the Middle East and other sub-tropical areas is rendered unviable due to excessive heat and drought. The focus of civilisation moves towards the poles, where temperatures remain cool enough for crops, and rainfall - albeit with severe floods - persists. All sea ice is gone from both poles; mountain glaciers are gone from the Andes, Alps and Rockies.
5C-6C
Global average temperatures are now hotter than for 50m years. The Arctic region sees temperatures rise much higher than average - up to 20C - meaning the entire Arctic is now ice-free all year round. Most of the topics, sub-tropics and even lower mid-latitudes are too hot to be inhabitable. Sea level rise is now sufficiently rapid that coastal cities across the world are largely abandoned.
6C and above
Danger of "runaway warming", perhaps spurred by release of oceanic methane hydrates. Could the surface of the Earth become like Venus, entirely uninhabitable? Most sea life is dead. Human refuges now confined entirely to highland areas and the polar regions. Human population is drastically reduced. Perhaps 90% of species become extinct, rivalling the worst mass extinctions in the Earth's 4.5 billion-year history.
In the SIM-air tool, all the calculations, including the conversion of emissions to concentrations, are conducted in Excel, using the source-receptor transfer matrix (SRTM). The transfer matrix, which enables the conversion of emissions to concentrations, is based on a dispersion model, which is not included the Excel analytical tool. This part of the calculations (generating the SRTM) is conducted outside the SIM-air tool and then transferred into Excel to enable further analysis to health impacts and optimization.
A number of dispersion models are available to support the development of SRTM; some are free for use with some technical support and some are available at commercial level. As usual, the dispersion models are very data intensive and need substantial training, before using the models for analysis.
At the training events, there was one question which was asked repeatedly is “access to a dispersion model, when the data available is minimum, experience is limited, and yet there is need for some rapid assessment”.
While we supplemented the need for a dispersion model with SRTM concept, the generation of the SRTM based on a dispersion model is now available. This paper describes a simplified dispersion model ATMoS-4.0 to generate SRTM using minimum data inputs for direct use in SIM-air for urban applications.
A pilot study was conducted in Delhi, India on October 3rd, 2009, covering ~160 km on road over 10 hours, recording PM10 and PM2.5 measurements at 1 min/1 sec intervals (full report).
During the experiment, over an 8 hour period, average PM10 pollution = 206 micro-gm/m3; PM2.5 pollution = 163 micro-gm/m3; Black Carbon pollution = 36 micro-gm/m3.
The collected data was interpolated over the Delhi map for visualization of the extent of exposure levels on a daily basis (shown below).
In the Northwest and West sections, traffic movement was slow, especially along the major corridors, along with construction activities, which contributed to higher ambient pollution levels. The Northwest and East sections also home for industrial areas. The South Delhi , which is more residential, tends to experience on average 100 to 200 mg/m3, which is well above the national and WHO health guidelines. See animated monitoring route.
For the current observations, utilizing the average concentrations over Delhi, assuming at least 30% of the population (~5,000,000) is constantly exposed to these levels, and a dose-response function from premature mortality (0.000014 cases/mg/m3/percapita), a back-of-the-envelope calculation yields an annual mortality rate of ~10,900.
This at willingness-to-pay rate of ~US$50,000.00 (~25,00,000.00 Indian Rupees) translates to US$545 millions in health damages due to premature mortality annually.
How many greenhouse gas emissions does negotiating a climate change treaty take?
That's the sound of climate change negotiations—and CO2 being released. All this talking is a seemingly significant source of greenhouse gas emissions and not just because negotiators have traveled to Copenhagen from all corners of the globe.
Whether it be the jets of world leaders—or shutting down the city to proceed in motorcades—transportation contributes 25 percent of global emissions. Then there's the vital warm and cozy hotels to house us here in this wintry town. In fact, the government of Denmark estimates that this climate conference will produce in its two weeks the equivalent greenhouse gas emissions of more than 600,000 Ethiopians.
The bulk of that is the more than 46,000 metric tons of carbon dioxide that comes just from all the flights into and out of Copenhagen airport. But the Danes have a plan. They've sent enough cash to Bangladesh to replace 20 old, heavily polluting brick factories with more modern facilities, which will lead to an annual savings of some 100,000 metric tons of CO2.
Of course, the only thing that would really justify all this "hot air" is a global, binding, verifiable, equitable agreement to combat climate change. But achieving that is a lot harder than buying a new brick factory in Bangladesh.
--David Biello, from Copenhagen Scientific American
******* More on the Dhaka Brick Kilns
The SIM-air working paper, SIM-21-2009, presents the results from the dispersion modeling of the brick kiln cluster emissions and their impact on the air quality in Dhaka, Bangladesh.
Image below presents monthly average PM2.5 concentrations in Dhaka, Bangladesh, with the brick manufacturing season (October-March) separated, which account for ~40-50% of the observed PM pollution in Dhaka city. Click on the image to enlarge view.
Now, we have a new study called "Space-Time Exposure Modelling System" (STEMS), as a pilot in London. The pilot focuses on modelling impacts on air pollution exposures, and associated modification in health risks to air pollution, of the London ‘Low Emissions Zone’ (LEZ). It builds on existing technologies, the airTEXT air quality forecasting and alerting system for London, www.airtext.info
"It was one of last symbols of the times when technology hadn't taken control of our lives, riding pillion didn't mean one person on the back seat and licence raj was very much in place. Almost everybody has a Bajaj moment to share."
If managing air pollution for better health is our primary goal, then we should monitor what we want to manage. Among the many pollutants, PM pollution is prevalent in most of the cities, and yet data available on ambient PM levels is limited for many reasons (read "hazy data").
A pilot study was conducted in Delhi, India on October 3rd, 2009, covering ~160 km on road over 10 hours, recording PM10 and PM2.5 measurements at 1 min/1 sec intervals. During the experiment, average PM10 pollution over a 8 hour period = 206 micro-gm/m3; PM2.5 pollution over a 8 hour period = 163 micro-gm/m3; Black Carbon pollution over a 8 hour period = 36 micro-gm/m3. The collected data was interpolated over a map of Delhi for visualizing the extent of pollution exposure on a daily basis (shown below).
To the Northwest and West parts of the city, traffic movement was slow, especially along the major corridors, at the construction sites, which contributed to higher ambient pollution levels. The Northeast and East parts of the city also home for industrial areas. In the South, which is more residential, tends to experience on average 100 to 200 mg/m3, which is still above the national and WHO health guidelines. See animated monitoring route.
For the current observations, utilizing the average concentrations over Delhi, assuming at least 30% of the population (~5,000,000) is constantly exposed to these levels, and a dose-response function from premature mortality (0.000014 cases/mg/m3/percapita), a back-of-the-envelope calculation yields an annual mortality rate of ~10,900.
This at willingness-to-pay rate of ~US$50,000.00 (~25,00,000.00 Indian Rupees) translates to US$545 millions in health damages due to premature mortality annually.
Article provides a simple explanation for 2-Stroke and 4-Stroke engines
(Source: Columbia Encyclopedia)
The Two-Stroke Cycle
The two-stroke engine is simpler mechanically than the four-stroke engine. The two-stroke engine delivers one power stroke every two strokes instead of one every four; thus it develops more power with the same displacement, or can be lighter and yet deliver the same power. For this reason it is used in lawn mowers, chain saws, small automobiles, motorcycles, and outboard marine engines.
However, there are several disadvantages that restrict its use. Since there are twice as many power strokes during the operation of a two-stroke engine as there are during the operation of a four-stroke engine, the engine tends to heat up more, and thus is likely to have a shorter life. Also, in the two-stroke engine lubricating oil must be mixed with the fuel. This causes a very high level of hydrocarbons in its exhaust, unless the fuel-air mixture is computer calculated to maximize combustion. A highly efficient, pollution-free two-stroke automobile engine is currently being developed by Orbital Engineering, under arrangements with all the U.S. auto makers.
The Four-Stroke Cycle
In most engines a single cycle of operation (intake, compression, power, and exhaust) takes place over four strokes of a piston, made in two engine revolutions. When an engine has more than one cylinder the cycles are evenly staggered for smooth operation, but each cylinder will go through a full cycle in any two engine revolutions. When the piston is at the top of the cylinder at the beginning of the intake stroke, the intake valve opens and the descending piston draws in the air-fuel mixture.
At the bottom of the stroke the intake valve closes and the piston starts upward on the compression stroke, during which it squeezes the air-fuel mixture into a small space at the top of the cylinder. The ratio of the volume of the cylinder when the piston is at the bottom to the volume when the piston is at the top is called the compression ratio. The higher the compression ratio, the more powerful the engine and the higher its efficiency. However, in order to accommodate air pollution control devices, manufacturers have had to lower compression ratios.
Just before the piston reaches the top again, the spark plug fires, igniting the air-fuel mixture (alternatively, the heat of compression ignites the mixture). The mixture on burning becomes a hot, expanding gas forcing the piston down on its power stroke. Burning should be smooth and controlled. Faster, uncontrolled burning sometimes occurs when hot spots in the cylinder preignite the mixture; these explosions are called engine knock and cause loss of power. As the piston reaches the bottom, the exhaust valve opens, allowing the piston to force the combustion products—mainly carbon dioxide, carbon monoxide, nitrogen oxides, and unburned hydrocarbons—out of the cylinder during the upward exhaust stroke.
Cooling and Lubrication of Engines
Most small two-stroke engines are air-cooled. Air flows over cooling fins around the outside of the cylinder and head, either by the natural motion of the vehicle or from a fan. Many aircraft four-stroke engines are also air-cooled; larger engines have the cylinders arranged radially so that all cylinders are directly in the airstream. Most four-stroke engines, however, are water-cooled. A water jacket encloses the cylinders; a water pump forces water through the jacket, where it draws heat from the engine. Next, the water flows into a radiator where the heat is given off to the air; it then moves back into the jacket to repeat the cycle. During warm-up a thermostatic valve keeps water from passing to the radiator until optimum operating temperatures are attained.
Four-stroke engines are lubricated by oil from a separate oil reservoir, either in the crankcase, which is a pan attached to the underside of the engine, or in an external tank. In an automobile engine a gear pump delivers the oil at low pressure to the bearings. Some bearings may depend on oil splashed from the bottom of the crankcase by the turning crankshaft. In a two-stroke engine the lubricating oil is mixed with the fuel.
I was listening to NPR and the story of "Concerned Scientists Vs. 'Superfreakonomics' Author". The author suggests some provocative ideas for addressing the problem of global warming, like pumping sulfur dioxide into the upper atmosphere to cool down the earth.
I do not approve of this approach. This shall remain a best seller on the amazon list and hope people don't take this too seriously.
On the silver screen in 2004, “The Day After Tomorrow” dramatized a possible scenario of an immediate calamity due to global warming and climate change and an overnight push to the ice age.
In the “Inconvenient Truth”, Al Gore was very persuasive on the contribution of human activity to the current levels of greenhouse gases in the atmosphere and the impending consequences via climate change, for which he won an Academy Award for best documentary feature film and shared the Nobel Peace Prize along with the Intergovernmental Panel on Climate Change (IPCC).
Thus, “global warming” and “climate change” have become common phrases, heightened the public awareness across the world, and created international threshold for immediate need for action.
So far, so good.
Recent projections of the IPCC estimate that by 2080, 1.1 billion to 3.2 billion people will be facing water scarcity; 200 million to 600 million, hunger; and two million to seven million more homes will be hit hard by coastal flooding. Between 75 and 250 million people in Africa alone will experience increased water shortages due to climate change by 2020. Although greater wealth may offset damage through adaptation in many nations, without the ability to pay for such measures the world's poor are likely to suffer more stress from climate impacts in the coming decades. Lord Stern, former chief economist at the World Bank, estimated the cost of climate change at between 5 per cent and 20 per cent of global gross domestic product.
Dr. James Hansen from NASA, renowned physicist in the field of climate modeling, concludes that far from aiming to limit rising CO2 concentrations to a ceiling of 450 ppm (parts per million), as currently suggested, the world should set a long-term target of getting back down to 350 ppm. A few decades with CO2 above that figure might not matter, but it would be foolish to allow CO2 to stay in the danger zone for centuries. The global average CO2 concentration was 385 ppm in 2008.
This morning, Dr. James Hansen sent out an email titled, "Sack Goldman Sachs Cap-and-Trade" and quote.. As I explain in my book "Storms of My Grandchildren" what is planned for Copenhagen is a selling of Indulgences, as in the Middle Ages when the Catholic Church sold forgiveness of sins. The Bishops were very happy (lots of moulah) and the sinners were happy (they could still go to heaven). The developed country sinners in Copenhagen will be paying moulah via "offsets" (many imaginary or unverifiable) and "adaptation" funds and the developing countries will be looking to collect as many billions as possible. Can't blame them for that, but it is plain as day that the global emissions are not going to take the rapid downward track that the science demands.
This is best explained by Annie Leonard in her "story of cap & trade.
The conference of the parties (COP) to the United Nations Framework Convention on Climate Change (UNFCCC) is meeting for the 15th time in Copenhagen, Denmark. While the goal is to establish an ambitious and effective international response to the climate change, the discussions are still bogged down by the economics of who will do what and how much. There is an increasing pressure on India and China to join an emissions capping agreement, which both parties have restrained from in the past, saying the rich and developed countries who lead the industrial revolution should take the lead and should agree for bigger cuts.
Among the few scientists, the leading voice for reengineering comes from Dr. Paul J. Crutzen, who won the Nobel Prize in Chemistry for formation and decomposition of Ozone. The theory revolves around blocking and reflecting the sun light by spreading sulphur-aerosols into the atmosphere. The immediate impacts of such an exercise not tested in a laboratory, but are already observed nature. The Mount Pinatubo eruption in the Philippines in 1991 cooled global temperatures by about half a degree Celsius for the next few years.
The aerosol plan is also cheap - so cheap that it completely overturns conventional analysis of how to mitigate climate change. In the past, Thomas C. Schelling, who won the 2005 Nobel Prize in economics, has pointed out how difficult it is to get vast international agreements - such as the Kyoto Protocol - to stick. But a geo-engineering strategy like sulphur aerosol changes everything.
Dr. Schelling argues that while the big emitters are bickering about the emission caps and whether or not to mitigate the greenhouse gases fast; who will stop a small nation like Maldives or Bangladesh from attempting to cool down the temperatures fast and cheap by pumping aerosols. At the end, this is the step they may have to take in their national interest, to save the millions of the poor and thousands of hectares of drowning land resources?
I hope it will not come to this.
In 1999 Movie, “The Matrix”, Neo “the one” learns that it is the humans who scorched the sky, in order to block the sun and stop the life support to the machines. The unintended consequences led to the end of humanity on earth, but they managed to block the sun.
While the short term measures like sulphur-aerosols are intended to provide immediate relief, this is only postponing the long term damage. The unintended impacts of higher sulphur in the atmosphere mean more incidences of acid rain and further ecosystem damage.
A recent study published by the Pacific Northwest National Laboratories, that bad air quality (due to aerosols) in the Eastern China is affecting the rainfall patterns, thus the country's ability to raise crops as well as contributing to health and environmental problems.
The interaction of policies and knowledge base to better understand the air pollution (aerosols) and climate change have not been sufficiently investigated and there is a tremendous potential for co-benefits.
Policy research aimed at clarifying the synergies and trade-offs in this field could help to develop instruments that work both ways. And in the mean time, hope that no radical measures are implemented for short term benefits and people will listen to the likes of Dr. James Hansen for stringent mitigation measures on the ground.
An article in Examiner states that the Beijing car population will reach the four million mark in December 2009 and the city averaged ~2,000 cars a day in 2009 to reach the mark. And yet, the authorities claim that "it was confident that the city’s air pollution wouldn’t worsen as the number of cars increased".
Call me lame, but I do not understand the math here. If something is polluted, and if you are adding something to the system without purging the old, how is this not worsening?
1. City just added 1 million cars in less than 28 months. Even if the new cars are Euro-IV complaint, they are still emitting something. What about all the cars that are pre-Euro IV, which are still on the road.
2. If the cars were running normally, then OK, at least they are serving the mobility function, but not if they are sitting in congestion. Our calculations show, on average a 20 min idling in the city can lead to an addition of up to 10 percent of the emissions which could have been avoided.
Get out of the cars. The air pollution (and other emissions linked to climate change) is severe along the corridors and worse during the rush hours, mostly due to congestion and idling emissions. A lot of energy is wasted every where, in US, China, Europe, India, and the rest of the World.
