30 years of climate talks: progress, pitfalls and a planet in peril

As leaders gather for the U.N. climate summit in Brazil this week – three decades after the world’s first annual climate conference – the data charting progress in the fight against global warming tells a sobering story. Despite years of negotiations, pledges, and summits, greenhouse gas emissions have climbed by a third since that first meeting; fossil fuel consumption continues to rise; and global temperatures are on track to breach thresholds scientists say will unleash cata