《澄社評論》關心地球暖化

■ 鄭天佐

科學家利用南極開採冰柱鑑定遠古大氣溫度，冰柱沈積物類似年輪，從不同深度冰柱氧氣同位素比可鑑定不同年代氣溫，冰內氣泡可用來分析溫室氣體含量，近代數據則透過直接溫度和衛星量測。科學家已經確立兩百年來地球表面溫度的異常快速上升，也發現大氣中的溫室氣體含量一樣異常增加中。他們更確立了大氣中溫室氣體含量與人類石化燃料使用量成正比，所以地球表面暖化源自產業革命後石化燃料的大量使用已無疑義。

絕大多數科學家認為地球表面溫度上升原因是溫室氣體，如二氧化碳、甲烷、和N2O等阻礙地面散熱所致。極少數科學家提出不同見解，或認為溫度變化在統計學變動範圍內，或是小冰河期的自然回溫，或是太陽釋放能量的變動，或是都市效應的擴充。

筆者未找到討論使用能源時釋放的熱能對地面溫度的影響資料，自己粗略計算估計地面溫度可上升約攝氏一度。

地球暖化會造成（一）南極、高山和冰河覆蓋冰層的薄化與退縮，北極浮冰的破碎，和海平面的上升，世紀末前可能升高一至六公尺，因全球一半人口居住在沿海一○○公里內，海面上升將牽動人口重新分佈。（二）天氣變化激烈，地面沙漠化，很多物種面臨絕滅，人類與物種必然會大遷移。（三）農漁業、植物和動物生態變動對人類經濟及民生活動會造成巨大影響。（四）疾病傳染、生態環境改變也會影響人類健康。

我們因應之道為：（一）訂定積極減碳時程，推動全民減碳運動：以宣導和教育培養民眾及企業界少用石化能源的習性。扶植再生能源產業，提高家電和生產機器能量效率，並訂定以價制量的新能源稅制，促成全民減少石化能源的使用，務必在五年內達到節省百分之十以上目標。（二）產業結構的調整：從現有製造業往服務、文化和智慧型產業轉型是今後政府應該推動和企業界應該思考的方向。（三）儘速完成核四的建造：從能源安全考量，核能是最可靠的主要和備用能源，我們必須在施工品質和運轉安全保證下，儘速完成核四的建造。最重要的是全民和政治人物積極思考因應之道，並趕快動起來制訂新能源政策，最可怕的是政府忽視問題的迫切性。（作者為中研院研究員）（自由廣場，1/26/07）

We must all realize that climate is a local issue

By Tsong Tien-tzou 鄭天佐

Taipei Times, Monday, Jan 29, 2007, Page 8

Scientists have drilled ice cores under the Antarctic to examine the climate in ancient times. The sediments inside the ice cores are like tree rings. Experts are able to understand the climate during different periods by comparing the oxygen isotopes inside ice cores from different depths, and even analyze the amount of greenhouse gases through the bubbles inside.

Based on historical data, scientists have confirmed that the temperature on the earth's surface has risen drastically over the past two centuries and that there has been an abnormal rise in the amount of greenhouse gases in the air. They have also confirmed a direct proportional relationship between the amount of greenhouse gases in the atmosphere and the use of fossil fuels, which means that there is no longer any doubt that global warming is a result of the widespread use of fossil fuels since the industrial revolution.

Most scientists believe that the temperature rise has been caused by greenhouse gases such as carbon dioxide and nitrous oxide which hinder heat dissipation.

A small minority of scientists have a different view, believing that the rise falls within the scope of statistical change. They believe it is a natural temperature rise following the end of a little ice age, changes in energy released by the Sun or an expansion of the urbanization effect.

I haven't been able to find any data on the effects of the heat released through energy use on global temperatures, but my rough estimate is that it may increase temperatures by about 1oC.

Global warming will have the following impact. First, the thinning and shrinking of the polar ice caps, ice and snow on high mountains and glaciers and the break-up of Arctic icebergs mean that the global sea level may rise by between 1m to 6m by the end of the century. Since half of the world's population lives within 100km of a coastline, this will lead to a redistribution of the population.

Second, drastic weather changes, land desertification, the extinction of numerous species and major relocations of humans and animals.

Third, changes in the agricultural and fishery industries and plant and animal ecology will have a deep effect on the human economy and livelihood.

Fourth, the spread of infectious diseases and changes to the ecological environment will affect human health.

We have the following options. First, set an aggressive schedule for a major carbon reduction campaign. We should inform and educate the general public and industry on how to use less fossil energy and promote the renewable energy industry. We should also improve the energy efficiency of electrical home appliances and production machinery while enacting new tax policies to regulate energy use and make people cut down on fossil fuels in order to cut energy use by at least 10 percent in five years.

The second option is to adjust industrial structure. The government should push for a move from manufacturing to the service, cultural and knowledge industries and industry should consider how to achieve this.

The third option is to complete the construction of the Fourth Nuclear Power Plant as soon as possible. From the perspective of energy safety, nuclear power is the most reliable alternative both as the main and a backup source of energy. Provided there are quality and safety guarantees, we should complete the plant as soon as possible.

Most importantly, both the general public and politicians should actively consider ways to respond to the issue and hurry to establish a new energy policy.

The most frightening aspect is that the government is ignoring the urgency of the matter.

Tsong Tien-tzou is a research fellow in the Institute of Physics at the Academia Sinica. Translated by Eddy Chang