EXTERNAL FORCES ACTING ON THE EARTH'S CLIMATE: AN APPROACH TO UNDERSTANDING THE COMPLEXITY OF CLIMATE CHANGE

摘要

The Intergovernmental Panel on Climate Change defines lifetime for CO_2 as the time required for the atmosphere to adjust to a future equilibrium state, and it gives a wide range of 5-200 years; however, a number of published data show a short lifetime of 5-15 years. This implies that anthropogenic emissions of CO_2 are sequestrated more easily than expected, suggesting it would be beneficial to look at other climate factors when making long-term predictions. Considering the magnitude and the time length (cycle), climate change can be interpreted as the result of the complex coupling of astronomic forces (e.g. the Earth's orbit and cosmic-ray flux) as well as terrestrial forces. Regarding the Earth's climate as a complex (nonlinear) system, it is necessary for the climate research community and policy makers to distinguish between variations caused by anthropogenic and natural occurrences, and the problem of how to do so arises.