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China’s average temperature in the past winter hit its lowest in 27 years, about 1 degree Celsius lower than normal. Other countries in Asia and Europe were also hit by cold temperatures and snowstorms. Many people wondered if the climate had stopped warming and started going cold.
But experts believe the long-term trend of global warming will continue, in spite of the cold winter. China will take the initiative in saving energy, reducing greenhouse gas emissions and switching to an environmentally friendly model of growth because this is the only way for the country to realize sustainable economic and social development.
Still warming
A single cold winter does not change the trend of global warming. Statistics from China and other countries throughout the world prove that in the past century the average land surface temperature has increased.
“There is no doubt that global temperatures have been on the rise in the past century, and global warming hasn’t stopped yet. It’s too early to draw a conclusion that global warming triggered by human activities has stopped or the world is going to turn cold,” said Luo Yong, Deputy Director of the National Climate Center of China.
Unlike global climate change, which has existed for decades, cold spells in an individual winter belong to a phenomenon related to weather changes. “Generally speaking, there are fewer cold days than in previous years as a result of global warming. But it is normal that cold spells can strike some places for some time,” Luo said.
Although cold spells were extremely active in Europe and Northeast Asia in the past winter, many places elsewhere, like North America, experienced high temperatures. December last year was the 12th warmest December on record, and January this year was the 19th warmest January. “So it is unconvincing to conclude that global warming has ceased just because temperatures in certain places in the past winter were lower,”said Luo.
The global average surface temperature has risen 0.74 degrees Celsius in the past century. Temperature increases have accelerated since the 1970s. 2010 was the warmest year in the past 100 years, and 2001-10 was the warmest decade in the past century.
2011 was the ninth warmest year since 1880, when people started to take weather records, according to the latest statement of the U.S. National Aeronautics and Space Administration. Nine of the 10 hottest years in the world’s weather record were after 2000. Monitoring results from the U.S. National Oceanic and Atmospheric Administration(NOAA) also showed the same tendency. The NOAA announced that 2011 was the warmest La Nina year since 1951. La Nina, characterized by unusually cold ocean temperatures in the eastern equatorial Pacific, often contributes to temperature drops around the globe.
The situation in China is similar. According to a climate change report China released in November 2011, the average temperature of China’s land surface has increased 1.38 degrees Celsius since 1951. 2007 was the warmest year during the past century in China, and 2001-10 was its warmest decade.
China’s average temperature in 2011 was 9.3 degrees Celsius, 0.5 degrees higher than the average temperature from 1971-2000, making 2011 the 14th warmest year since 1951.
Ding Yihui, Deputy Director General of China’s Climate Change Experts Committee, said while the average land surface temperature is on an upward trajectory, there can be short- or long-term fluctuations. It is normal that a certain period is colder or warmer than usual.
For example, 1920-40 and 1970-2000 were relatively warmer periods, while the first two decades in the 20th century and 1950- 70 were colder periods. According to World Meteorological Organization standards, only when the average temperature during 30 years shows obvious changes compared with the average temperature of the previous 30 years, can a new climate change tendency be confirmed, Ding said.
Since the Industrial Revolution started in the 18th century, greenhouse gas concentrations in the atmosphere and the average land surface temperature have both increased. The trend is clearer in the Northern Hemisphere, which has more human-generated greenhouse gas emissions, than in the Southern Hemisphere. This is evidence that greenhouse gas emissions from human activities are probably a major cause of climate change, Luo said.
Despite possible benefits to agriculture, global warming threatens the world with a rising sea level, which will cause great harm to coastal areas. “If global warming proceeds slowly in the next 50 to 100 years, it will create both advantages and disadvantages. But if it goes too fast for ecological, economic and social systems to adapt to the changes, its consequences will be unfavorable and even disastrous,” Luo said.
Ding believes it is still hard to say whether global warming will escalate in the near future. This is possible as greenhouse gas emissions keep going up. But countries around the world are intensifying efforts to cut emissions, and the role of oceans in regulating temperatures remains unknown. It will take several more years to draw a confirmed conclusion on the pace of global climate change, he said.
Putting the pace and effects of climate change aside, experts say efforts to save energy and control greenhouse gas emissions will be a boon for China’s economy. A “green transformation” will not only help protect the environment but also contribute to China’s industrial upgrading.
Green transformation
Ding said whether the globe becomes colder or warmer, changing the unsustainable economic development mode to realize a green transformation is a good choice for China. The country should adjust its economic and social development plans to promote industries with low greenhouse gas emissions and environmentally friendly practices.
“The key is to promote green development and low-carbon economy to accelerate the transformation of its development mode,” he said.
Du Xiangwan, a research fellow with the China Academy of Engineering Physics, said there are indeed some countries in the world trying to force China to take on excessive emission reduction obligations as a tactic to restrain China’s rapid economic development. But he stressed “energy conservation” and“emission reduction” are not merely trendy concepts in international climate negotiations, but are indispensable to China’s healthy development.
He said China’s rapid development has made tremendous achievements during the past 30 years. However, the current economic development mode is unsustainable because pressure on the environment and energy resources keeps increasing.
“China has now come to a stage at which an economic transition is essential,” Du said. The efficiency of resource utilization must be enhanced, while resource consumption must be decreased. In the past, the country’s economic development created big environmental problems. Now, China must pursue environmentally friendly growth by promoting innovation and encouraging high-valueadded industries.
Since 2001, China’s energy consumption has grown rapidly. It increased 2.2 times from 2001 to 2010, putting great pressure on resources and the environment. China’s GDP accounted for 9.5 percent of the world’s total in 2010, but its energy consumption represented 19.5 percent of the world’s total. Its greenhouse gas emissions were nearly one quarter of the global total. China’s energy consumption, pollution discharge and carbon emissions per unit of GDP all stand at high levels.
The traditional mode of economic development is the root cause of high resource consumption, said Du. For example, the United States became a developed country after over 200 years, and has high per-capita energy consumption. The country’s population is less than 5 percent of the world’s total, but its annual energy consumption represents 20 percent of the world’s total. If every country in the world were to reach such a development level, this would require the resources of four to five Earths, which would be a disaster for the whole world.
China should realize its modernization with per-capita energy consumption significantly lower than that of developed countries like the United States. This is why China needs to follow a new path of industrialization, Du said. This new path, featuring green and low-carbon development, calls for energy saving, the efficient and clean utilization of fossil energy, and the development of nonfossil energy. “This is a win-win energy strategy for both the economy and the environment, which can satisfy the demand of China’s sustainable development,” said Du.
Fossil fuels account for about 90 percent of China’s current primary energy consumption, in which coal occupies about 70 percent. The efficient and clean utilization of coal will be a key point for saving energy and reducing emissions. Currently 55 percent of China’s oil consumption relies on imports. The country must save oil and develop alternatives to oil. Since natural gas is a relatively clean source of fossil energy, increasing the use of natural gas should be part of China’s energy strategy, Du said.
Non-fossil energy includes renewable energy and nuclear energy. Non-fossil energy occupies less than 10 percent of China’s energy structure. By 2015, this proportion is expected to reach 11.4 percent. By 2020, non-fossil energy will account for 15 percent of China’s energy mix, and by 2050, about 40 percent. “In this way, China will perfect its energy structure and reduce greenhouse emissions,” Du said.
Since global warming is still happening, China must take measures to limit emissions and adapt to changing climate conditions. “The active way of coping with climate change brings new development opportunities to China. China’s green transformation will contribute to the healthy and sustainable development of China and the world,” Du said.