How can we see climate change?

Warmer temperatures are just one of the many signs of climate change. NASA analyzed 29,000 different records of natural systems and found that 90% of them experienced changes linked to warming.(1),(2)

“Climate change is occurring and is already exacerbating hazards”
– Andrew Castaldi, Swiss Re America’s Head of Catastrophe Perils

Putting all the pieces together, along with more technical clues, scientists from NASA, NOAA, and hundreds of other institutions have strong evidence of human-driven climate change.

1. Carbon dioxide concentrations grew about 25% in just the last 50 years

Around the world, people release more than 2.3 million pounds of carbon dioxide into the air per second.(3) Trees and the ocean absorb about half of it, leaving the remainder to build up in the air. Scientists estimate today’s levels of carbon dioxide have not been seen on Earth for at least 800,000 years.(4),(5)


Source: University of California, San Diego & NOAA

2. Warming rate unseen in over 1,300 years(7)

Record high temperatures have accompanied rising levels of carbon dioxide. About half of human carbon dioxide emissions between 1750 and 2010 occurred in the last 40 years.(8) And nine of the past 10 years were the hottest on record, with 2014 being the hottest ever.(9) The current rate of warming is unprecedented in over 1,300 years and Stanford scientists say we’re on track for rates unseen in over 65 million years.(9),(10) Temperatures and carbon dioxide are not perfectly synced because temperatures are sensitive to year-to-year swings from volcanoes, ocean patterns, and other natural sources.(11)


Sources: NOAA Temperatures and NOAA CO2

3. The ocean has become 30 percent more acidic(12)

Although carbon dioxide can help plants grow, it makes the ocean toxic for many marine animals. The extra carbon dioxide in the air is being absorbed by the ocean and altering its chemistry. Billions of tons of manmade carbon dioxide have been absorbed by the ocean, causing it to become 30% more acidic since 1850.(13),(14)

Buoys all over the world are seeing clear changes in the ocean. Data from one in Hawaii is shown below:


Sources: NOAA Temperatures and NOAA CO2

4. Oceans Rising Faster than Any Time in 6,000 Years(15)

Satellites and other tools clearly show that the ocean is rising– and scientists have figured out why. There are two main reasons: polar ice is melting and water expands when it warms.(16),(17) It may not seem like much but the gradual rate of increase has been unmatched in over 6,000 years.(18)


Sources: NASA

5. Polar ice losing weight of an aircraft carrier—every 8 seconds

Polar ice melt is another consequence of a warmer world. Land ice on Greenland is melting at a rate of roughly 8,175 tons per second and 4,658 tons per second in the Antarctic.(19) The ice loss is equal to the weight of a Nimitz class aircraft carrier, the largest warship ever built, every 8 seconds.(20),(21)



Sources: NASA

6. Arctic ice losing the size of Kentucky every two years

Since 1996, Arctic sea ice has been losing about 19,500 square miles each year.(22) At the same time, Antarctic sea ice surface area is increasing, but not enough to offset the losses in the Arctic.(23) The reason the Antarctic is growing may also have ties back to climate change.

7. More severe storms costing the United States billions

The number of heavy downpours in the United States has steadily increased since the 1950s.(24)


Sources: American Meteorological Society

These storms are also taking a toll on taxpayer wallets: “billion-dollar” severe storm recoveries are also increasing.(25)


Sources: NOAA

8. Shorter winter seasons

The U.S. is experiencing fewer freezing days (and a shorter winter season). The shift has had a sizeable impact on the U.S. ski industry.(26),(27),(28) Top ski destinations such as the Sierras and Rockies are the most affected, lost about 19 operational days since the early to mid-1900s. Artificial snow is not a substitute either because it requires below-freezing temperatures.(29)


Sources: Kenneth Kunkel, Cooperative Institute for Climate and Satellites, NCSU, NOAA NCDC

9. Wildfires are on the rise

Firefighters are dealing with unprecedented conditions. Four times as many large forest fires burn in the U.S. West every year compared to 30 years ago.(33),(34) If that wasn’t enough, the fire season is more than two and a half months longer, about a 40 to 50 percent jump.(35),(36),(37)


10. Plant and animal behavior

Plants and animals are responding to warmer temperatures by adapting migration, breeding, and other behaviors.(30),(31),(32) Birds, for example, are shifting their homes to cooler climates. Adaptation and relocation is not a solution for all birds: The National Audubon Society estimates that nearly half of U.S. bird species are at risk.(38)




  1. NASA: Human Impact
  2. NASA: Is Current Warming Natural?
  3. Oak Ridge National Laboratory
  4. NASA: Carbon Cycle
  5. Global Warming
  6. Climate Central: The Last Time CO2 Was This High, Humans Didn’t Exist
  7. NASA: Evidence
  8. USA Today
  9. NASA: Evidence
  10. Stanford University
  11. US Geological Survey: Volcanoes
  12. NOAA: What is Ocean Acidification?
  13. USGS: Monitoring and Assessment of Ocean Acidification in the Arctic
  14. NOAA: What is Ocean Acidification?
  15. Weather Channel
  16. National Geographic: Sea Level Rise
  17. NOAA: Sea Level
  18. NASA: Ocean Cooling
  19. NASA: Land Ice
  20. S. Navy: Aircraft Carriers
  21. Royal Museums Greenwich
  22. NASA: Global Sea Ice Diminishing Despite Arctic Gains
  23. NASA: Global Sea Ice Diminishing Despite Arctic Gains
  24. American Meteorological Society
  25. NOAA: Billion-dollar Weather Events
  26. Business Insider
  27. New Hampshire Union Leader
  28. Vail Daily
  29. Climate Central
  30. National Geographic: Earliest Blooms
  31. CNN
  32. University of North Carolina, Chapel Hill
  33. National Academy of Sciences
  34. World Resource Institute: Western US Wildfires
  35. CBS: Age of Megafires
  36. ClimateCentral: Wildfires 2012
  37. Science Magazine
  38. National Geographic: Climate Change May Put Half of North American Birds at Risk



  1. Sea Level Rise – NASA
%d bloggers like this: