Are there still rooms left for us?

This year the planet Earth reaches its landmark human population, 7 billion! And projected to be 8 billon in year 2030 and 9 billion in year 2050. Homo sapiens perhaps consist of the largest mammal population in the earth. The topic was highlighted by the January 2011 issue of National Geographic, which showed a tremendous acceleration of human population growth in the past millenium of the 20th century. The number of mega cities with population exceeding one million has increased from a mere 3 in 1800 (Beijing had 1.3 million then together with Tokyo and London) to a staggering 442 in year 2010 with Asia having most crowded cities. Population growth was in no doubt one of the central focuses of the media this year. Many media sources discussed the consequence and solutions to accomodate increasing number of humans. Building vertical cities become a future trend given that it’s after all a reality.

(Figure adopted from

With the advent of industrialization and advance of medicine, human life style morphed from nomadic and periodic migration to modern city dwelling. The former life style was at the mercy of mother nature and gradually phases out in most human society. The latter provides a long-term residence but in the meantime features more frequent and more damaging pattern of short-term human travelling for business and pleasure as well as trading transportations in air, land and ocean.

Aggravating the situation, consumption culture imposes much more stress on the environment. Mass consumption as a vehicle drives the global economy, labor market and international trading, and large-scale consumption is also a determinant for policy making, a pressure for foreign relations and a motivation for scientific and engineering research.

How much pressure the Earth can uptake for our consumption desires? Is there a tipping point that leads to a catastrophe?

Feel free to breath the dirty air

The infamous Beijing smug stroke again a few days ago. The situation was so dire that even some Chinese official acknowledged that China should adopt a better standard to measure the air quality and to report the results to the public. However, air pollution is not something new to ordinary Chinese as well as the lack of government effort to protect citizens from such hazard.

This time the authority was embarrassed by data released from the Beijing Embassy of the United States. The Embassy has installed meters on a roof to measure the level of fine particulates PM2.5 (particules smaller than 2.5 micron) and updated the information hourly via a Twitter thread. Instead, the Chinese government only reports the level of PM10, particulates bigger than 10 micron, and conveniently omits the PM2.5. It’s scientifically well known that PM2.5 particulates penetrate deeply into the lung beyond the protection by cilia, and presumably do much sever damage to human health. Health complications of inhaling PM2.5 particles might include pulmonary and cardiovascular disease such as asthma and bronchitis. More science still needs to be done to differentiate the effects of different types of PM2.5 particles.

In response to the data from the US Embassy, Chinese official asks the public not to trust the readings from the US embassy roof (I know the existence of this device perhaps more than two years ago from reading James Fallows blog at

A more interesting report emerged from New York Times. China’s high authorities in Beijing are protected from breathing the dirty air by some extravagant air purifiers.

NASA published a satellite data map about PM2.5 pollution worldwide from year 2001 to year 2006 (see below). At anywhere in the world, you might inhale numerous PM2.5 particles per breath. According to the satellite image, the number stays several fold higher if you happen to be living in China which has some highest readout in the map.