Finally, the energy security problem has been complicated by the problem of global climate change. As the science has become increasingly clear, climate change is now a major political issue at the global and national levels.
最后，全球气候变化问题也让能源安全问题复杂化了。正当科学日益清楚之际，气候变化现在已经是全球和各国的一个主要政治问题。