JPL BLOGS
Inside Views on Outer Space
Hear from scientists, engineers and other experts as they offer a fascinating look at JPL missions, science and history.
Earth Right Now | September 26, 2016
Watching our climate 100 miles from shore
Baffin Island, specifically, the largest island in Canada.
“What are we doing all the way out here?” I thought. If I looked out the left side of NASA’s modified G-III aircraft, I could see Canada out the window—Baffin Island, specifically, the largest island in Canada, part of its northeast territory. And if I looked out the right side, I could see the west coast of Greenland. We were pretty much halfway between the two, right in the middle of Baffin Bay, and I was surprised.
At a glacial pace
I went over to where Flight Engineer Terry Lee kept the map of all the scheduled drop positions and stared at it for a while. She’d marked with a green highlighter the places where she’d already released science probes through a tube in the bottom of the plane. (Hahahah, yes! There’s a hole in the plane through which Aircraft eXpendable Conductivity Temperature Depth (AXCTD) probes leave the aircraft to travel 5,000 feet down to the sea surface and then another 1,000 meters into the ocean, sending back data as they go.)
I looked out the window as we flew on. Icebergs dotted the seascape. Each one had once been part of a vast ice sheet that’s been around for hundreds of thousands of years. Each one had moved – at a glacial pace, mind you – from the interior, down through one of the many fjords that slice through the Greenland coastline, and finally out to sea, where they would ultimately melt away. The ‘bergs were large, and it was fun to fly over them and look at their perfect whiteness against the stunning blue sea. All of us would gather on one side of the plane as we passed over a ‘berg, and then quickly jump to the other side to look for it again as we passed by it. But even though there were hundreds of icebergs floating around out there, Baffin Bay is vast — more than 250 thousand square miles. So, in the grand scheme of things, the icebergs seemed inconsequential, incapable of affecting the ocean salinity more than a small amount.
Real-time data
As I was listening, I could see temperature and salinity values arriving in real-time on the monitor. “Wow, no way!” I exclaimed. “That’s insane.” All the way in the middle of Baffin Bay, 100 miles offshore, the ocean was fresher on the surface. I watched the salinity values increase as the probe sank. The temperature profile also reflected a scenario of near-zero-degree water at the surface with 3- to 4-degree ocean water below. That upper layer is Arctic Ocean Water, which is way less salty than the warmer North Atlantic Ocean Water that lies beneath it.
I walked back to look at the yellow dots on the map of the scheduled probe drops one more time. We were as far away from the coast as we would be; the rest of the drops were closer to shore. I wondered how the temperature and salinity profiles in the coastal waters would compare to those from the open ocean.
And the point of the mission flooded my mind again. I looked out the window, across the stretch of Baffin Bay at the Greenland coastline, where groups of icebergs dotted the horizon. In this vast expanse, no one’s done this before, no one knows what this ocean water is like, and we are about to find out.
Find out more about Oceans Melting Greenland.
View and download OMG animations and graphics.
Thank you for your comments.
Laura
TAGS: CLIMATE, OCEANS, MELTING, GREELAND, NASA, JET PROPULSION LABORATORY, JPL
Earth Right Now | September 8, 2016
An ice-tronaut prepares
Greenland is one of the few places that’s harder to get to than outer space
I’m going to Greenland. I told my brother, and he replied, “Oh cool, I’m headed to Ireland.” That’s the typical response, as if Greenland were just some place one could book a ticket to, with commercial airports, and hotels, and restaurants and stuff. But … no, Greenland is different. It’s actually not an independent country, for example. (It’s a territory of Denmark.)
The other response I keep getting is that dumb, corny comment about it not being green. So it seems like the only thing we collectively understand about Greenland is that it’s a place to go and it has a hypocritical name.
But that is just so wrong. My husband and I finally got on the same page this morning when he opened the Google Maps satellite view of Kangerlussauq Airport, where I’m scheduled to land. “Oh,” he said. “It’s a barren dirt strip in the middle of nowhere and nothing.”
At last, an acknowledgement of the truth. The only place that’s harder to get to than Greenland is outer space. I know that sounds funny, but I’m not even kidding. (Okay, okay, Antarctica is also hard to get to, along with the Marianas Trench. Ugh.)
I first became aware of how little we know about Greenland when I was creating NASA’s Global Ice Viewer for our climate website. I found shots from Alaskan glaciers that dated all the way back to the late 1800s for the gallery. Gents with top hats and ladies in bustles with Victorian cameras stood on the ice. But Greenland? Photos taken before the 1980s are extremely rare.
And while most people understand that increased atmospheric temperatures have been melting the ice sheet from above, global warming has also been increasing ocean temperatures. And this means the ocean waters surrounding Greenland are also melting the ice sheet from around its edges.
Which is the reason I’m headed up there with NASA’s Oceans Melting Greenland (OMG) campaign in the first place: to measure the temperature and salinity of those unknown waters. See, the fresh water that flows into the ocean from ice melt is about 0 degrees and less dense, so it floats right at the sea surface. The North Atlantic Ocean Water is about 3 or 4 degrees, salty and denser, so it sits right below the fresh melt water. And these two waters don’t really mix much. When the 3- or 4-degree North Atlantic Ocean Water gets in contact with Greenland’s ice sheet, it’s warm enough to melt it.
But no one knows the melt rate yet. No one.
Even though Greenland’s melting ice sheet impacts each and every one of us right now. The rate of ice melt will determine how much sea level rise we’re going to get, 5 feet or 10 feet or 20, everywhere, all over planet Earth, not just in Greenland, but at coastlines near you and me.
This is where that whole NASA “exploring the unknown” theme comes in. Next week, the OMG team (including yours truly) will be in Greenland on NASA’s G-III aircraft. We’ll spend five weeks flying around the entire coastline, measuring the salinity and temperature of the coastal waters by dropping 250 Aircraft eXpendable Conductivity Temperature Depth (AXCTD) science probes through a hole in the bottom of the plane. The reason we’re going in September is that’s the warmest time of the year in the ocean, the ice will reach its lowest extent and we’ll be able to measure as much of the coast as possible. The plan is to repeat the same mission for five years to find out what the melt rate is and how much that rate is increasing.
Am I excited? Yes, beyond. Aside from the science preparation, it took months and months of personal prep. I passed a Federal Aviation Administration medical exam, then got trained in First Aid, CPR, AED, hypoxia, disorientation, survival, and hearing conservation, and then had to buy steel-toed shoes, which are required to fly on that NASA plane. Today, I am psyched beyond belief.
Why else would anyone work so hard to do something? Just like the rest of the team, I hope our work really makes a difference.
TAGS: GREENLAND, EARTH, NASA, JPL, JET PROPULSION LABORATORY, GLOBAL WARMING, OCEANS
Earth Right Now | August 10, 2016
TEDx Talk: Run toward the challenge of climate change. I dare you.
Everyone you admire, everyone who’s accomplished greatness, faced obstacles along the way. Think about it. Everyone. The most impressive athletes, artists or public figures found their way to success by moving through and overcoming roadblocks.
Today, as my morning jog turned into a run and then a sprint, I felt my power and strength as a woman to keep pushing forward. No. Matter. What.
At the entrance to NASA’s Jet Propulsion Laboratory where I work, there’s a sign that says “Dare Mighty Things.” The way I see it, that sign is talking directly to me. “I dare you,” it says. Not to try something easy, but to run toward the challenge of climate change with confidence, strength and courage. And now I dare all of you.
TAGS: TEDX TALK, CLIMATE CHANGE, JET PROPULSION LABORATORY, NASA
Earth Right Now | July 5, 2016
How NASA prepares future climate scientists for careers in the sky
NASA's Student Airborne Research Program trains future climate scientists.
We receive a lot of questions, especially from students, asking us for information about how to get a job at NASA. Well, there’s more than one way to get hired here. But one of the most awesome methods we have of training young scientists and preparing them for potential hire here (or a great position anywhere) is by recruiting university undergraduates for our Student Airborne Research Program (SARP).
SARP is our eight-week summer program for college seniors with academic backgrounds in engineering or physical, chemical or biological sciences and an interest in remote sensing. We select about thirty students based on their academic performance, their interest in Earth science and their ability to work in teams. These students receive hands-on research experience on NASA's DC-8 airborne science laboratory. Yup, they get to fly on a modified NASA plane out of NASA’s Armstrong Flight Research Center, in Palmdale, Calif., where they help operate instruments onboard the aircraft and collect samples of atmospheric chemicals.
Did I already say “awesome”? Oh right, I did. Well, I’ll say it again: Awesome.
Many students apply hoping to gain more research experience for graduate school. The whole air sampling team, which is exactly what it sounds like, collects air from around the plane in canisters as it’s flying through different locations and altitudes at different times. The air enters the plane from the outside through an inlet, a pipe sticking out of the plane. The student scientists open the canisters, allowing air from outside the airplane to suck into the can. Then they take the air samples back to the lab at the University of California, Irvine, for analysis and interpretation.
SARP students analyze the air samples for hydrogen, carbon monoxide, carbon dioxide, methane, hydrocarbons, nitrates, oxygenates and halocarbons. Research areas include atmospheric chemistry, air quality, forest ecology and ocean biology.
Once the airborne data has been collected and analyzed, the students make formal presentations of their research results and conclusions. Over the past seven years, the program has hosted 213 students from 145 U.S. colleges and universities. And this year we look forward to helping our latest crop of SARP students gain research experience on a NASA mission, work in multi-disciplinary teams and study surface, atmospheric and oceanographic processes.
Find out what SARP students thought about their experience here.
Find out more about SARP and other Airborne Science Programs here.
Thank you,
Laura
SARP is part of NASA Earth Expeditions, a six-month field research campaign to study regions of critical change around the world.
TAGS: NASA, CLIMATE, FUTURE, CAREERS
JPL | December 20, 2010
Red, Red Moon and Other Lunar Eclipse Phenomena
A lunar eclipse occurs when the Earth is positioned between the sun and the moon. Although the Moon passes through the Earth's shadow, the lunar disk remains partially illuminated by sunlight that is refracted and scattered by the Earth's atmosphere.
Refraction is the bending of light that occurs when the rays pass through media of different densities (our atmosphere is more dense near the surface and less dense higher up). Scattering of sunlight by molecules of air also deflects the light into different directions, and this occurs with much greater efficiency at shorter (bluer) wavelengths, which is why the daylight sky appears blue. As we view the sun near sunrise or sunset the light traverses a longer path through the atmosphere than at midday, and when the air is relatively clear, the absence of shorter wavelengths causes the solar disk to appear orange.
Tiny airborne particles, also known as aerosols, also scatter sunlight. The relative efficiency of the scattering at different wavelengths depends on the size and composition of the particles. Pollution and dust in the lower atmosphere tends to subdue the color of the rising or setting sun, whereas fine smoke particles or tiny aerosols lofted to high altitudes during a major volcanic eruption can deepen the color to an intense shade of red.
If you were standing on the Moon's surface during a lunar eclipse, you would see the Sun setting and rising behind the Earth, and you'd observe the refracted and scattered solar rays as they pass through the atmosphere surrounding our planet. Viewed from the Earth, these rays "fill in" the Earth's shadow cast upon the lunar surface, imparting the Moon's disk with a faint orange or reddish glow. Just as we sometimes observe sunrises and sunsets with different shades of orange, pink or red due to the presence of different types of aerosols, the color of the eclipsed lunar disk is also affected by the types of particles that are present in the Earth's atmosphere at the time the eclipse occurs.
TAGS: EARTH, EARTH SCIENCE, GLOBAL CLIMATE CHANGE, GLOBAL WARMING, NASA, LUNAR ECLIPSE
My Big Fat Planet | December 6, 2010
Unchained Goddess: Frank Capra Knew
You might think from the amount of “climate science debate” that is given airtime in the U.S. media that it’s undiscovered territory. But it’s not. The science is very well established and goes back a long way. Global warming is not a new concept.
The Victorians knew about it. John Tyndall (born 1820) knew about it. So did Svante August Arrhenius. In April 1896, Arrhenius published a paper in the London, Edinburgh and Dublin Philosophical Magazine and Journal of Science entitled “On the influence of carbonic acid in the air upon the temperature of the ground.” (Arrhenius referred to carbon dioxide as “carbonic acid” in accordance with the convention of the time.)
Arrhenius’ paper was the first to quantify how carbon dioxide contributed to the greenhouse effect — carbon dioxide warms up the Earth by trapping heat near the surface, a bit like swaddling the planet in an extra blanket. Arrhenius was also the first to speculate about whether changes in the amount of carbon dioxide in the atmosphere have contributed to long-term variations in Earth’s climate. He later made the link between burning fossil fuels and global warming.
Another person who “knew” some time ago was Frank Capra. Graduating from Caltech in 1918, he went on to become a famous filmmaker responsible for “It’s a Wonderful Life” and other movies. But one that stands out, at least for nerds like me or people with an interest in climate change is “Meteora: The Unchained Goddess”, released in 1958.
Made for Bell Labs, this most awesome educational film speaks of “extremely dangerous questions”:
Dr. Frank C. Baxter: “Because with our present knowledge we have no idea what would happen. Even now, man may be unwittingly changing the world’s climate through the waste products of his civilization. Due to our release through factories and automobiles every year of more than six billion tons of carbon dioxide, which helps air absorb heat from the sun, our atmosphere seems to be getting warmer."
Richard Carlson: "This is bad?"
Dr. Frank C. Baxter: "Well, it's been calculated a few degrees rise in the Earth’s temperature would melt the polar ice caps. And if this happens, an inland sea would fill a good portion of the Mississippi valley. Tourists in glass bottom boats would be viewing the drowned towers of Miami through 150 feet of tropical water. For in weather, we’re not only dealing with forces of a far greater variety than even the atomic physicist encounters, but with life itself."
In 1958, they knew about the effects of heating up the planet. In the 1800s they knew about it. Today, the biggest challenge facing climate scientists lies in predicting how much our climate will change in the future. It’s not a trivial task, given how complicated the climate system is — we can barely predict in detail more than a week’s worth of weather. We’re not viewing Miami through bottomed-glass boats yet, but we’re already beginning to see some of the predictions of global warming — melting sea and land ice, sea level rise, more extreme weather events, changes in rainfall and effects on plants and animals — be borne out.
Thanks to OSS and Discovery News for the tip.
This post was written for "My Big Fat Planet," a blog hosted by Amber Jenkins on NASA's Global Climate Change site.
TAGS: EARTH, EARTH SCIENCE, GLOBAL CLIMATE CHANGE, GLOBAL WARMING, NASA
JPL | October 15, 2010
Taking On Water Resource Issues
Worldwide today, it is estimated that nearly 1.1 billion people live without access to adequate water supplies and about 2.6 billion people lack adequate water sanitation. Improved understanding of water processes at global and regional scales is essential for sustainability.
Researchers at JPL recently launched the Western Water Resource Solutions website to highlight activities that apply NASA expertise and data to water resource issues in the western United States.
One focus area for this new site is the hydrologic cycle and using global satellite observations of the Earth to improve our understanding of water processes on a regional and local level. The western United States is expected to bear the brunt of impacts to water resource availability because of changing precipitation patterns, increasing temperatures, and a growing population. California is already starting to feel the impacts and is taking action to develop new adaptive management practices to ensure a safe and reliable water supply, while maintaining healthy ecosystems throughout the state.
NASA researchers at Ames Research Center, the Jet Propulsion Laboratory, and Marshall Space Flight Center are currently working with water managers to apply NASA expertise and data to water resource issues in California. The project partners with universities, agencies and other stakeholders, to utilize information from a number of sources, including existing ground observations and models.
This project is only one of several NASA initiatives aimed at providing actionable scientific information on water quality and the water balance worldwide. These other projects include development of better estimates of snow pack, groundwater monitoring, soil moisture and evapotranspiration, water quality, and monitoring fragile levee systems.
In addition to raising awareness about current water resource challenges, the new website highlights NASA's capability to use satellite and airborne data to help solve some of these challenges.
Learn more about the Western Water Resource Solution Group at: http://water.jpl.nasa.gov/
Written as part of Blog Action Day 2010
TAGS: EARTH, CLIMATE, BLOG, ACTION DAY, WATER RESEOURCES, NASA
