China must overcome major challenges in order to achieve the target set by the State Council last year to reduce carbon dioxide emissions per unit of GDP by 40-45 percent from the 2005 level by 2020. Stern steps are clearly mapped out in the 12th Five-Year Plan (2011-2015), which shows China's firm resolve to address climate change.

Economic development and improving people's livelihoods are the top priorities for many developing countries, including China. With a population of 1.3 billion, China's per capita GDP is just over $3,000. By United Nations' standards, 150 million Chinese live below the poverty line and China shoulders the burden of improving people's livelihoods.

Even though China is currently at a crucial stage in its endeavor to build a xiaokang (well-off) society - an important stage of industrialization and urbanization - the nation will not follow the same path as most developed countries, which made little effort to control emissions during their own industrialization and urbanization.

Economic growth determines the intensity of energy consumption and carbon dioxide emissions per GDP. With economic development and improvement in people's living standards, it will take active measures to control greenhouse gas emissions.

China's urbanization level is only 45 percent. It will take 30 years to reach 75 percent given the current growth rate of 1 percent a year. Even more daunting for China, the urban population will increase by 450 million from now to 2040, which is equivalent to 1.5 times the population of the United States.

Rapid urbanization creates increasing demand for urban infrastructure and housing, employment, consumption and energy. Emissions will increase as people's consumption increases.

Given there are 100 square meters of buildings per capita - which covers residential houses and hospitals, schools and other public facilities - even if the life span of a building is 100 years, 1.4 billion sq m of new buildings will be needed every year. Improving people's living standards, maintaining and retrofitting infrastructure, will all put additional pressure on controlling greenhouse gas emissions in the future.

Along with economic and social growth and the improvement in people's living standards, China must also shift from industrialization to modernization.

To achieve its carbon intensity reduction target, the total non-fossil energy consumption will be equivalent to 675 million tons of coal in 2020, an increase of an equivalent of more than 500 million tons of coal compared to 2005.