The 1990s were the hottest decade on record. Permafrost is melting. Glaciers are disappearing. Coral reefs are dying. Lakes and rivers are freezing later and thawing sooner.
Oceans are higher.
Droughts are longer. Weather is wilder. Our great-grandchildren could face difficult if not disastrous consequences with water and food supplies, flooding, disease. Mostly just putting out more hot air - greenhouse gases such as CO2 and methane. This isn't just an economic or ecological issue.