By NASA Administrator Charles Bolden and
NOAA Administrator Kathryn Sullivan
Climate change is one of the most pressing issues of our generation and it affects every person on Earth. Tracking the changes in the global climate is the basis for understanding its magnitude and extent.
Today’s announcement that NASA and NOAA scientists have determined that 2015 was the hottest year in recorded history underscores how critical Earth observation is. The NOAA-NASA collaboration has served the country very well, from the origin of space-based remote sensing for weather forecasting to the Earth system monitoring and science that are so crucial to tackling the issues of our times. This announcement is a key data point that should make policy makers stand up and take notice — now is the time to act on climate.
The modern temperature record dates back to1880, and 2015 was the warmest year by a long shot.
There has been a lot of talk about the strengthening El Niño in the Pacific Ocean and how that might be supercharging temperatures. El Niño did likely play an important role – but more significantly, 2015’s record temperatures are the result of the gradual, yet accelerating, build-up of carbon dioxide and other greenhouse gases in Earth’s atmosphere. Scientists have been warning about it for decades and now we are experiencing it. This is the second year in a row of record temperatures and what is so interesting is that the warmest temperatures often occur the year after an El Nino, like in 1998 compared to 1997.
Fifteen of the 16 warmest years on record have now occurred since 2001. Temperatures will bounce around from year to year, but the direction of the long-term trend is as clear as a rocket headed for space: it is going up.
This record-breaking moment is a good time to take stock of what we know of our changing planet and why it is important for NASA, NOAA and other federal agencies to continue studying Earth’s climate and how it is changing:
- Sea levels are rising – nearly three inches in the past two decades alone. The successful launch earlier this week of the NOAA-led Jason-3 mission will continue our 23-year record of measuring sea level change from space with remarkable precision. In the coming years and decades, our work to understand how quickly seas are rising will be vital to coastal cities in the U.S., millions of people around the world who live in low-lying areas, and to NASA’s own facilities at Kennedy Space Center, where we will one day launch astronauts to Mars, and other affected facilities such as the Stennis Space Center, Wallops Flight Facility and Michoud Assembly Facility.
- The Arctic ice cap is shrinking. In the 1970s and 80s, NASA scientists pioneered techniques to measure the extent of sea ice at the poles. That new ability quickly gave way to the realization that the Arctic ice cover – which plays a significant role in the planet’s climate and even the weather we experience in the U.S. – is retreating and growing thinner.
- NOAA’s global drifting buoy program and other NOAA and international ocean temperature and land surface temperature measurements have provided the means to measure the temperature at the Earth’s surface, so critical to our survival.
- Ice sheets and glaciers worldwide are shedding ice. Greenland is losing about 300 billion tons of ice per year, according to measurements from NASA’s GRACE mission. Observations from the agency’s Operation IceBridge have helped confirm rapidly accelerating changes in the West Antarctic Ice Sheet and the dramatic retreat of glaciers in Alaska. Given the pace of these changes and their significance for the climate and sea level rise, we need close and continuous monitoring. In 2017, NASA will launch two missions – GRACE-FO and ICESat-2 – that represent a major refresh of our capabilities to observe how ice sheets and glaciers are changing.
Rising temperature is not an isolated effect of rising greenhouse gas levels, and scientists are still studying the full implications of a warmer world. How might patterns of drought and precipitation change? Will ecosystems and species be able to adapt to human-induced climate change? What might these changes mean for wildfires, agriculture and the economy?
Climate change isn’t a problem for the future. Earth’s climate is changing now. At NASA, we use our unique vantage point from space to study the planet as a whole system. NOAA’s scientists are on the ocean, land and in the sky collecting data that help bring clarity. Our job is to answer these kinds of questions, to make the measurements needed to get to those answers and to provide our knowledge and our data freely so the world can address this fundamental challenge.