Scientists warned of climate change over a century ago, and now Catalonia has lost some land to rising sea levels. Global temperatures have increased by 3 degrees Celsius over the past 100 years due to increased population and pollution. Cities like Venice are at risk of flooding, while some regions like Russia may see agricultural benefits from climate change. Leaders need to take action to reduce emissions and consumption to mitigate the future impacts, which include stronger hurricanes, drier conditions in Catalonia, and potentially needing to pay for clean air.