Life. It's the one thing that, so far, makes Earth unique among the thousands of other planets we've discovered. Since the fall of 1997, NASA satellites have ...
When you think of NASA you probably think of this
But as soon as we made it beyond the limits of our atmosphere, one of the first things we did
was turn our cameras around at look at this
The first US satellite was launched in 1958.
That’s eleven years before Neil Armstrong became the first person to walk on the moon.
Explorer 1, built at the Jet Propulsion Laboratory,
initiated a long legacy of satellites meant to take our understanding of Earth to new heights.
In 1997, NASA launched a satellite that began a twenty-year continuous global record
of the very thing that, as far as we know, makes Earth special: life.
While most satellite missions capture data on the physical characteristics
of our planet's climate and weather, others allow us to measure life itself.
The most complete view of global biology to date.
The greatness of this data set is kind of hard to explain.
It allowed me to understand the ocean in such an organic way.
That’s the voice of oceanographer Dr. Ivona Cetinic.
Dr. Ivona Cetinic. Ivona and the rest of the NASA Goddard Ocean Ecology Lab
help oversee the twenty-year data set.
If you take a closer look at this animation,
you’ll see what looks like a repetitious ebb and flow on the land and surface of the ocean.
We’re actually watching the planet breathe.
About half of the total photosynthesis occurs on land and half in the oceans
That’s Dr. Compton Tucker
who pioneered satellite monitoring of vegetation on land.
The spring and summer months kick off the growing season for plants on land
illustrated in dark green
and tiny microscopic plant-like organisms in the ocean called phytoplankton
seen in light blue.
They take carbon dioxide out of the atmosphere and use it for energy,
causing the total amount of carbon in the air to drastically drop.
The opposite is true during colder months.
During winter in the Northern Hemisphere -- which is home to most of Earth's land plants
carbon in the atmosphere increases, as plants go dormant.
And then there are extremes zones in the ocean.
Purple patches are nearly devoid of any phytoplankton – they’re basically deserts at sea
while the red zones tell us that there’s either a high concentration of phytoplankton
hugging the coastline or our satellite sensors are picking up
on another input changing the color of the water.
We have a marvelous biological diversity of plants and animals both on the land
and also in the oceans.
But hold on.
If we have amazing biological diversity of plants and animals,
why do scientists spend all their time observing plants?
You know how they say you are what you eat?
In the same way, if you want to understand life in the ocean
you have to start from the base and that’s what phytoplankton is.
If phytoplankton are changing then the whole ecosystem will change.
The changes that Ivona is talking about are much easier to see
when we can study a continuous global record.
And that means not only being able to look into the past, but also into the future.
It's this long-term data set that not only allows us to see exactly what's happening
but to be able in so much better way to predict what's going to happen.
A global perspective gives scientists the power to forecast events
like harmful algal blooms, disease outbreaks and even famine.
Maybe one of the most useful applications of the data
is its ability to show us where we’ve been.
In twenty years the planet has changed in noticeable ways
and this data set gives us a visualization to prove it.
Arctic greening coupled with retreating Arctic sea ice
are probably one of the most well-known examples of this.
If you look at the higher northern latitudes you see in the white where there’s snow
and that then moves further north and recedes.
It’s then followed by very, very green colors,
because plants are really photosynthesizing in those dark green periods
Scientists think there are likely trillions of planets
yet Earth is still the only planet we know of with life.
With that in mind,
our habitable home world seems evermore fragile and beautiful
when considering the vastness of unlivable space.
I have several friends and acquaintances who are astronauts.
They all say the same thing.
When they’re in orbit on the space shuttle or in the International Space Station
and they look down at the Earth, they see one climate, one planet.
We’re all in this together,
and we need to work together to make sure
life as we know it continues on this wonderful planet.