Global leaders must create jobs in the renewable energy sector so that the costs of transitioning from fossil fuels do not exacerbate economic inequalities, Ban Ki-moon, the former United Nations secretary general, said on Wednesday on the sidelines of the COP26 climate summit in Glasgow. “What is absolutely necessary at this time — it is critical now — is for governments to increase their ambition level, not only in clean energy, but creating millions of new green jobs for the people,” Mr. Ban, the U.N. leader from 2007 to 2016,…