China's Past and Future: Climate Change, Agriculture and Human Carrying Capacity
Fan Yuqian, Laura Luo Lan, Rachel Qiu Weiwei, Vivien Xu Xiu, Sophie
Master of Arts in China Development Studies The University of Hong Kong 14/12/2012 1
As the third largest country in the world, China covers a territorial area of 9.6 million km2 , stretches some 5,026 kilometers across the East Asian landmass. With such a big coverage, the climate in China is extremely diverse. There are five major climates in China, Alpine climate, temperate continental climate, temperate monsoon climate, sub-tropical monsoon climate and tropical monsoon climate. Part of China’s northernmost province, Heilongjiang, has a subarctic climate. Tremendous differences in latitude, longitude, and altitude give rise to sharp variations in precipitation and temperature within China. For example, a large degree of the timing of the rainy season and the amount of rainfall throughout the country is dominated by monsoon winds, which are caused by differences in the heat absorbing capacity of the continent and the ocean. Since the monsoon winds get weaker as it moves to the inland, there is less precipitation in inland China than that in the costal area. The area located in the south of Qin Mountains experiences abundant rainfalls about 1000 millimeters while in the desert areas in northwest China, there is rarely any precipitation throughout the year. Furthermore, the temperature differences in China are also huge. In winter, the temperature could reach -40℃ in Northern China, while it is 10℃ in Southern China at the same time. From the 1960s, China has experienced a series of climate change, including temperature rising and unstable precipitation. These changes have had great impact on China’s agricultural production and thus affected China’s human carrying capacity. Because of China’s large territory, the impacts of climate change are different from 2
Northern China to Southern China, and not all of them are negative. This paper will discuss the climate change and agricultural production in Northern China and Southern China separately, aiming to find out the relationship between climate warming, agricultural production and human carrying capacity.
Figure 1. Temperature Change in China (Source: Piao et al., 2010)
Figure 2. Regional Trend in Temperature (Source: Piao et al., 2010)
Climate warming, Precipitation and Agricultural Distribution Over the past five decades, China has experienced a strong warming, and this situation has been supported by continuous measurement from 412 meteorological stations all over the country. Figure 1 indicates the trend of temperature changing in China. From 1960s to 2010, the temperature in China has increased by 1.2℃, the trend of temperature change is rising, and it reached a peak in late 1990s. After 2000, though the temperature has slightly dropped, it is still much higher than that of 1980s. 3
In addition, the seven warmest years all occurred during the last two decades. In the mean time, the chart in Figure 1 shows that the summer warming rate is about 0.01℃ per year while that of the winter warming is about 0.04℃ per year, almost 4 times of the summer warming. Winter warming is stronger than summer warming in China. There is also regional diversity in temperature changing. Figure 2 illustrates that in Northern China, especially Inner Mongolia, the temperature has been enhanced 0.4℃
Figure 3. Precipitation Trend in China (Source: Piao et al., 2010)
Figure 4. Regional trend in precipitation (Source: Piao et al., 2010)
per year, while in the southwest China the temperature only has 0.15℃ rise per year. (Piao et al., 2010). The temperature changing in China is different from region to region. Precipitation, which is very important to agriculture, also varies from season to season and region to...