1 big thing ... 30-year alarm: Climate change reality
On June 23, 1988, in the midst of a heat wave, NASA climate scientist James Hansen issued a stark warning to the Senate energy committee: Human-caused global warming was already detectable, and would grow far worse with time.
Why it matters: He was right.
- Since 1988, the Lower 48 states have warmed at a rate of 5.2 degrees Fahrenheit per century, and the globe has warmed at a rate of 3.2 degrees Fahrenheit per century, NOAA found.
- The five warmest years on record have all occurred in the 2010s.
Now, we're living in the era of global warming consequences. Here are just a few:
- In the Arctic, sea ice is disappearing, permafrost is melting and Greenland is losing ice into the sea.
- Around the world, precipitation is now falling in more intense bursts. Heat waves are more frequent and severe.
- In the Western U.S., wildfires are getting larger and more destructive amid hotter, drier summers, and earlier snowmelt in the spring.
Record high temperatures are now outpacing record lows by a ratio of more than 2-to-1 in the U.S. And the air carries more moisture than it used to, which gets wrung out in storms like 2017's Hurricane Harvey, which was the most extreme rainstorm in U.S. history.
- The world is on track for more than 5 degrees Fahrenheit of warming by the end of this century, depending on emissions trends.
- The latest climate projections also call for global average sea levels to rise by at least 1 to 4 feet by 2100.
We own this ... The planet's climate system is like a giant ocean liner: It can't be turned around instantly. We're stuck with decades of sea level rise and extreme weather events, even if we take aggressive action to prevent the worst-case scenarios.
"The clock has run out in terms of avoiding damaging changes — they have already begun. At this point, we are into damage control." — Michael Oppenheimer, Princeton climate scientist who testified with Hansen in 1988
Most climate scientists say there's still a small window to avoid the doomsday scenarios:
- It will take both cutting greenhouse gas emissions, and making our communities more resilient.
- Technological advances and energy markets have already resulted in emissions cuts, as natural gas, solar and wind power grow in popularity.
- Companies, including tech giants like Google and Facebook, are investing in clean energy even as Washington rolls back climate change regulations enacted by the Obama administration.
- Cities and states are acting, too.
- Transformative technologies may be around the corner.
The bottom line: This is happening. It's largely because of us, and it's getting worse.
Explore, share Harry Stevens' graphic of the spinning globe.