The Earth is a living, breathing planet.
Climate
change can be hard to recognize up-close, on a human scale — the
storms, floods, and heat waves it causes can seem, on a year-to-year
basis, like slightly more intense versions of past events
If you zoom out, however, the effects of climate change become more apparent.
That’s
what NASA has been doing for decades now. Through its satellites,
particularly the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), the US
space agency is able to track planetary-scale events over long periods
of time.
And
then through the collapsing magic of time-lapse videos, all that
information becomes startlingly comprehensible to the untrained eye.
For
the 20th anniversary of the SeaWiFS satellite, NASA recently released a
time-lapse compilation of the global footage it gathered.
“These
are incredibly evocative visualizations of our living planet,” said
Gene Carl Feldman, an oceanographer at NASA’s Goddard Space Flight
Center in a press release.
“That’s the Earth, that is it breathing every single day, changing with
the seasons, responding to the Sun, to the changing winds, ocean
currents and temperatures."
The short video shows
continental and ocean-wide changes occurring, visible as shifting
concentrations of color. Some of the changes are of the seasonal
variety, such as plants coming back to life in the spring. Others are
stoked by accumulating carbon in the atmosphere.
As
the ocean warms and absorbs more carbon, for example, the bedrock of
the marine food chain is being threatened — microscopic phytoplankton.
“As
the surface waters warm, it creates a stronger boundary between the
deep, cold, nutrient-rich waters and the sunlit, generally nutrient-poor
surface waters,” Feldman said in the press release.
As a result, phytoplankton are often unable to receive nutrients and “biological deserts” form.
“It’s
not just the amount of food, it’s the location and timing that are just
as critical,” Feldman added. “Spring bloom is coming earlier, and
that’s going to impact the ecosystem in ways we don’t yet understand.”
These changes are expected to cause reactions across marine ecosystems, according to NASA.
On
land, one of the most visually striking sequence of images took place
in Alaska. Some of the state’s biggest forest fires in history occurred
in 2004 and 2015, NASA notes.
“These
fires were amazing in the amount of forest area they burned and how hot
they burned, ”said Chris Potter, a research scientist at NASA’s Ames
Research Center in the press release. “When the air temperature hits 90
degrees Fahrenheit in late May up there, and all these lightning strikes
occurred, the forest burned very extensively — close to rivers, close
to villages — and nothing could stop it.”
Ultimately,
the 20 years worth of images distill the slow-moving, sometimes
irrevocable, changes that are happening to the planet and they could
serve as a wake-up call, especially in the US, where climate action remains a stubbornly partisan issue.
Earlier
in the year, the US was battered by three powerful hurricanes that gave
a glimpse of the future of climate change — more extreme storms — and prompted enormous relief efforts.
Real-time
disasters can serve as catalysts for policy change. But taking the
long-view, as NASA does, provides more solid footing for action.
Global
Citizen campaigns on the Global Goals, which call on countries to
mitigate climate change. You can take action on this issue here.
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