Notes：
greenhouse gas グリーンハウスガス，温室（効果）ガス;
straightforward 簡単な，分かり易い;
the amount of carbon debt （地球温暖化）炭酸ガス排出量;
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Have you ever heard that coal-burning power plants cause more greenhouse gases than any other kind of plant? A new, six-month study in Massachusetts found that wood-burning power plants may actually release more gases than coal-burning plants over time. The conclusion isn’t as straightforward as it might seem because the calculation is based on the amount of carbon removed by forests and the amount of carbon debt (the carbon put into the atmosphere when the trees are burned). In other words, because there are fewer trees to clean the air, burning trees can actually be worse than using coal. (by Prof. Carmella Lieske)
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