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Dr. Amber Jenkins

Amber Jenkins is Editor of NASA's Climate Change website and project manager of the Center for Climate Sciences at NASA's Jet Propulsion Laboratory. She's passionate about climate change, science and science communication.

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Climate change chronicles from NASA


Entering unknown territory
Carbon dioxide milestone passed
May 16, 2013
posted by Amber Jenkins, NASA Jet Propulsion Laboratory
14:45 PDT
Entering unknown territory

Imagine there are no people. Imagine a planet where the sea level is about five to 40 meters (16 to 131 feet) higher than normal. Imagine a planet that is hotter and wetter. Imagine, worldwide, it’s roughly 3 to 4 degrees Celsius (5.4 to 7.2 degrees Fahrenheit) warmer than today. And the North and South poles are even warmer still – as much as 10 degrees Celsius (18 degrees Fahrenheit) hotter than today.

Welcome to the Pliocene. That was the Earth about three to five million years ago, very different to the Earth we inhabit now. But in at least one respect it was rather similar. This is the last time that carbon dioxide (CO2) levels were as high as they are today.

On May 9, 2013, CO2 levels in the air reached the level of 400 parts per million (ppm). This is the first time in human history that this milestone has been passed. A preliminary daily average reading of 400.03 ppm was reported by the U.S. National Oceanic and Atmospheric Administration (NOAA), which operates the Mauna Loa Observatory in Hawaii where these measurements are made. While 400 sounds like just another number whose meaning is hard to grasp – similar to, say, world population recently hitting seven billion – these things do resonate, says Dr. Gavin Schimdt of NASA’s Goddard Institute for Space Studies. “People respond to anniversaries – why is 10 years after 9/11 more worthy of note than nine or 11 years? The importance of crossing 400 ppm is simply that it allows us to mark the occasion, and to demonstrate to the future that we knew where we were headed."

CO2 is the most important man-made greenhouse gas, which means (in a simple sense) that it acts like a blanket trapping heat near the surface of the Earth. It comes from the burning of fossil fuels such as coal, oil and natural gas, as well as deforestation. The level of CO2 in the atmosphere has risen from around 317 ppm in 1958 (when Charles David Keeling began making his historical measurements at Mauna Loa) to 400 ppm today. It’s projected to reach 450 ppm by the year 2040.

One of the problems is that CO2 lingers, both in the atmosphere and in the oceans (where it is being absorbed and acidifying the waters, with potentially big impacts on marine life). More than half of the CO2 is removed from the atmosphere within a century, but about 20 percent remains in the air for many thousands of years. Because of slow removal processes, even if we massively reduced our emissions of CO2 right now, atmospheric CO2 would continue to increase in the long-term. The CO2 we emit today, and that we have emitted since the advent of the Industrial Revolution, has long-term consequences that future generations will have to live with.

Some scientists, like NASA’s James Hansen, argue that CO2 must be limited to around 350 ppm in order to prevent “dangerous” climate change. As Hansen wrote in a 2008 paper, “If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced … to at most 350 ppm.”

To some, crossing the threshold of 400 ppm is a signal that we are now firmly seated in the “Anthropocene,” a human epoch where people are having major and lasting impacts on the planet. Because of the long lifetime of CO2, to others it means we are marching inexorably towards a “point of no return,” into territory that is unknown for the human race.

To hear what NASA scientists are saying about this milestone, click here.

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Ask the expert
How is climate change shaping the type of space exploration NASA does?
April 30, 2013
posted by Holly Shaftel
11:59 PDT
Ask the expert
Image by Jenny Mottar, NASA Headquarters

In this series on "Big Fat Planet," we answer reader-submitted questions about Earth's climate. The following is from Dr. Duane Waliser, who specializes in climate dynamics and modeling. He is the chief scientist of JPL's Earth Science and Technology Directorate and an adjunct professor in the Atmospheric and Oceanic Sciences Department at UCLA.

Question: How is climate change shaping the type of space exploration NASA does?

As global climate change becomes more evident, NASA’s satellite program for studying and monitoring our home planet becomes increasingly important. There are two key areas toward which NASA satellite measurements can contribute:

1.  Monitoring changes in the Earth’s climate.  Global climate change occurs slowly relative to weather and even to the change of seasons throughout the year. Changes known to be related to global climate change--increased atmospheric carbon dioxide and other greenhouse gases (including water vapor), sea level rise, and the melting of Arctic sea ice and the Greenland and Antarctic ice sheets--are so gradual that it takes many years, even decades, to characterize and quantify them. 

Given that satellite missions typically last on the order of three to 10 years, NASA often needs to consider launching copies of some instruments, as current versions age and fail. Continuity in our satellite observations is important for maintaining long records of key climate indicators, such as those listed above.  Having long and continuous records of these is critical for monitoring the effects of climate change, helping determine how we can best adapt to them, and assessing whether measures to limit its effects are working as expected.

2.  Improving our understanding of global climate change key processes. Simply monitoring some of the climate change indicators listed above doesn’t provide enough information for scientists to fully understand and characterize the problem and consequences. 

For example, only observing sea level rise doesn’t illuminate all the key processes that might be involved in determining the rate at which it is rising; these include sea level rise, the melting of ice sheets and glaciers, warming of the ocean, the continents’ and shorelines’ slow response to ice sheet melting and sea level rise, etc.  Similarly, it is critical to understand how water vapor and clouds respond to climate change, as these help determine the amount of future temperature warming that might be expected to result from increasing the amount of greenhouse gases in the atmosphere.

Knowing "how the Earth’s climate works" is vital to making projections of future warming and the associated impacts using very sophisticated computer models of the Earth’s climate.  For such projections to be useful, they have to accurately represent the Earth’s climate system.

Thus, some of NASA's satellite program focuses on developing new observations to illuminate how the Earth's climate system works and to reduce uncertainties in global models used for climate projection.

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Getting past 'I’m smart, you’re stupid'
Thoughts on finding a better way to engage people in science
April 25, 2013
posted by Laura Faye Tenenbaum
09:03 PDT
Getting past 'I’m smart, you’re stupid'
A teacher-eye view of Tenenbaum's oceanography's class. If your audience doesn't look engaged, then your talk is boring.

Laura Faye Tenenbaum is a science communicator at NASA's Jet Propulsion Laboratory and teaches oceanography at Glendale Community College.

I spend a lot of time asking students, audiences at speaking engagements, and other members of the public about their thoughts on science and I’ve noticed a theme that runs across all education levels, from deans and education administrators to lawyers and college students. “Sure, I like science,” people sigh, or “I used to like science when I was a kid.”

Often I hear positive descriptions of science: “It’s creative, fun, open, and interesting,” muddled with tired, old stereotypes: “Science is sterile, movies portray scientists as loners lacking social skills, it’s too complicated, I’m just not good at science.”

In the last few years, there has been an upsurge of websites, outreach opportunities, new media products and treatises about ways to improve public perception and public engagement in science. Nevertheless, the relationship between the public and the scientific community remains estranged. Scientific and academic communities have the habit of focusing inward, seeking engagement from those who are already engaged, while overlooking a portion of the public that feels cut off.

Professors are still in the outdated habit of failing half the class as a protocol to promote rigor, and our scientific community is made up of those who found a way to conform in this atmosphere. Failed students don’t merely vanish: they become our neighbors, our fellow citizens. They influence society. As a community of scientists and science educators, are they failing us or are we the ones who are failing them? Are we closing the door to people who may bring something creative, are we locking ourselves in?

Science-themed videos land in my inbox daily, tagged with notes like “this is great” on products that are boring or unmemorable and have few clicks. It’s not enough for us to pat ourselves on the back for our excellent work; it’s the public that ultimately judges the quality of our products. If you’re presenting a talk and you look at the faces of your audience and their eyes are glazed or they’re texting, then your talk is boring. If your online product isn’t getting thousands of hits then you need to re-evaluate and make changes. You will know if your message resonates in a meaningful way if you get invited back, referred, liked, shared, and remembered.

We need to maintain the rigorous content of scientific principles while at the same time engage a broader audience so that the scientific message resonates in a more meaningful way for more people. Having a Ph.D. and doing research is one way to participate in science, but not the only way. Yes, our students and our public must raise the bar on their intellectual capacity, and who wouldn’t want to participate in expanding their brainpower? But it’s us—the scientists, communicators, and educators—who also need to raise our own standards and expand our own capacity to find a way to connect.

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Simple wisdom
Arnold urges the Southwest to heed scientists' warnings
April 17, 2013
posted by Holly Shaftel
08:28 PDT
Simple wisdom
Arnold Schwarzenegger gave a few humorous opening remarks at the otherwise-sober National Climate Assessment public forum. (Credit: USC/Price)

Guest blogger Holly Shaftel is climate.nasa.gov's editorial assistant and social media specialist.  She is pursuing a master's degree in public administration at USC.

“As I get a little bit older and wiser, I realize that I’m less and less of a machine.”

In case you couldn’t guess, those words came from “The Governator,” or the former California Gov. Arnold Schwarzenegger, who hosted a public comment forum that I attended last week at the University of Southern California (USC) for the recently drafted National Climate Assessment Report. The report focuses on climate change’s projected impacts on the U.S., and this forum brought attention to the Southwest (our country's hottest and driest region). 

As I sat amongst a suit-wearing, predominantly male audience, the atmosphere felt somewhat stiff. But the Governator’s quip seemed to put us at ease before we began to absorb the findings on this serious, life-threatening matter.

The chairman of the USC Schwarzenegger Institute (in partnership with the USC Center for Sustainable Cities) likened the report to a doctor’s yearly physical—only the doctors, in this case, are climate researchers.

“The National Climate Assessment is our physical,” he said, underscoring the need to listen to expert diagnoses before the country has its own “heart attack.”

The “doctors” at the April 8 forum covered many critical issues. The quantity of information was overwhelming at times, but here were a few predictions that stood out. For example, if we continue at the current emissions rate:

  • “Megafires,” which burned between 40,000 and 60,000 acres in Arizona and New Mexico in 2011, will likely occur more frequently and rampantly.
  • The bark beetle epidemic, for which drought and high temperatures create favorable conditions, will kill off more trees (“forest thinning”) of all breeds and elevations.
  • Aggravated urban irrigation water shortages, which could shift Southwest crop demands northward, will likely “displace growers and impact communities.”1
  • Average temperatures will climb in the Southwest as much as 9.5 degrees Fahrenheit by 2100 (based on 1971 and 1999 data).2

Furthermore, I’m guessing prospects for the land of golden opportunities (or, as The Governator calls it, “Cah-lee-for-nee-uh”) were particularly interesting to the room, not only because it’s our home, but also because of our state's gargantuan economy. Here are two examples of what could happen to California:

  • Winter flooding, erosion, and sea level rise will impact the coast.  “All these tech giants are vulnerable,” a Bay Area-based co-author remarked, referring to Silicon Valley organizations, like Apple and Google, whose communication products many rely on every day.
  • High surface temperatures will likely increase mortality rates, particularly for children up to 5 years old and for people of color in impoverished communities.

These are just some examples of the probable forthcoming damage. By the end of the talk, a part of me wanted to bury my head in sand to cease listening to these grueling findings. But on the flip side, I knew that wouldn’t do me—or anyone on this majestic planet—any good.

I listened to the commentators from political, private, scientific, and academic (students and professors) backgrounds, and their views often aligned with what The Governator implied: If we don’t take care of ourselves and our planet by following expert advice, we could end up in an irreversible situation. It’s simple wisdom, and I got the vibe that many were willing to move forward to help avoid those worst-case scenarios.

References

  1. National Climate Assessment Report, Chapter 20, p. 702
  2. Ibid., Chapter 20, p. 689

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Ask the expert
Is it too late to reduce climate change?
February 18, 2013
posted by Dr. Amber Jenkins
15:07 PST
Ask the expert

Chip Miller
In this new series on "Big Fat Planet," we will answer selected questions about Earth's climate submitted by readers. Recently, a reader asked: "Is there still time to reduce climate change, or is it too late?" The following answer is from Dr. Chip Miller, a researcher specializing in remote sensing of carbon dioxide and other greenhouse gases at NASA’s Jet Propulsion Laboratory. He is principal investigator of the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) and was deputy principal investigator for NASA's Orbiting Carbon Observatory satellite mission, which was designed to measure atmospheric carbon dioxide from space.


Question: Is it too late to reduce climate change?

This is a question that has been asked many times and many studies have investigated similar questions: What level of climate change is "acceptable"? What constitutes "dangerous interference" in the climate system?

The short answer is that it's not too late to act, but our past actions may have already locked in certain outcomes and action is needed to avoid more substantial impacts in the future.

In the 1990s and early 2000s it was generally felt that a doubling of carbon dioxide (CO2) in the atmosphere compared to pre-industrial levels – that is, CO2 concentrations increasing to about 500 parts per million (ppm) – was "acceptable." However, the series of studies from the Intergovernmental Panel on Climate Change (IPCC) has found that as climate models improve, average worldwide surface temperature is projected to increase well beyond the "acceptable" level of 2.0 degrees Celsius (3.6 degrees Fahrenheit) by 2100. (See the IPCC website for the reports and most recent information.)

Jim Hansen (head of NASA’s Goddard Institute for Space Studies) has been one of the more outspoken advocates of curtailing CO2 emissions immediately to return atmospheric CO2 levels to about 350 ppm (the level of carbon dioxide that was in the air in the late 1980s). The challenge here is that even if human emissions of CO2 were cut to zero today, there is an inertia in the climate system that would continue for hundreds to thousands of years as the system attempts to re-equilibrate. (See Hansen's Royal Society paper, “Climate change and trace gases,” for more details.)

Michael Oppenheimer [Professor of Geosciences and International Affairs at Princeton University] and colleagues have taken a different approach to assessing climate change risk – they define the likelihood of certain environmental outcomes for different levels of atmospheric CO2 accumulation. (See their 2002 Science paper, "Dangerous climate impacts and the Kyoto Protocol," for a look at three potential outcomes at different CO2 levels.)


Further reading:

Perception of climate change,” J. Hansen, M. Sato & R. Ruedy, Proceedings of the National Academy of Sciences (6 August 2012); doi: 10.1073/pnas.1205276109.

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Rising seas
What do they mean for the California coast?
January 15, 2013
posted by Dr. Amber Jenkins
09:57 PST

video platformvideo managementvideo solutionsvideo player

Dr. Josh Willis, ocean guru at NASA's Jet Propulsion Laboratory, spoke to TV channel KCET recently about what sea level rise will mean for California and our coasts. Here's the interview.

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In essence: Science boiled down
Seafloor affects Arctic ice and clouds
January 8, 2013
posted by Dr. Amber Jenkins
14:11 PST
In essence: Science boiled down

An interesting recent paper from Dr. Son Nghiem at NASA’s Jet Propulsion Laboratory and colleagues finds that the bottom of the Arctic Ocean controls the pattern of sea ice thousands of feet above on the water’s surface. The seafloor topography exerts its control not only locally, in the Bering, Chukchi, Beaufort, Barents and Greenland Seas, but also spanning hundreds to thousands of miles across the Arctic Ocean. 

How? The seafloor influences the distribution of cold and warm waters in the Arctic Ocean where sea ice can preferentially grow or melt. Geological features on the ocean bottom also guide how the sea ice moves, along with influence from surface winds.

Interestingly, the study also links the bottom of the Arctic Ocean with cloud patterns up in the sky. The ocean bottom affects sea ice cover, which affects the amount of vapor coming from the surface of the ocean out into the air, which in turn influences cloud cover.

The researchers, who also come from NASA's Goddard Space Flight Center, the Applied Physics Laboratory and the National/Naval Ice Center in the U.S., use sea ice maps taken from space with NASA’s QuickSCAT satellite, as well as measurements from drifting buoys in the Arctic Ocean. They compare the sea ice and seafloor topography patterns to identify the connection between the two.

Bottom line:

Since the seafloor does not change significantly over many years, sea ice patterns can form repeatedly and persist around certain underwater geological features. So computer models need to incorporate these features in order to improve their forecasts of how ice cover will change over the short- and long-term. This ‘memory’ of the underwater topography could help refine our predictions of what will happen to ice in the Arctic as the climate changes.

Source:

Seafloor Control on Sea Ice,” S. V. Nghiem, P. Clemente-Colon, I.G. Rigor, D.K. Hall & G. Neumann, Deep Sea Research Part II: Topical Studies in Oceanography, Volumes 77-80, pp 52-61 (2012).

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Pick of the pics
The Earth at night
January 7, 2013
posted by Dr. Amber Jenkins
10:41 PST
Pick of the pics
Earth at night, as seen by the Suomi National Polar-orbiting Partnership (NPP) satellite, a joint effort by NASA and the National Oceanic and Atmospheric Administration (NOAA). Courtesy of NASA Earth Observatory and NOAA National Geophysical Data Center.

This is a new image of our planet at night, as taken by a new NASA and National Oceanic and Atmospheric Administration (NOAA) satellite orbiting above us. Scientists recently unveiled this global composite image (and the one below), constructed using cloud-free nighttime images. They show the glow of natural and man-made phenomena across the planet in greater detail than ever seen before. City lights can tell us about how humans have spread across the globe.
Many satellites are equipped to look at Earth during the day, when they can observe our planet fully illuminated by the sun. But with a new sensor onboard the NASA-NOAA Suomi National Polar-orbiting Partnership (NPP) satellite launched last year, scientists now can observe Earth's atmosphere and surface during nighttime hours.

For more Earth at night images, see this article.

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Finding the plot
Real-life climate stories
November 27, 2012
posted by Dr. Amber Jenkins
14:57 PST

Climate change makes headlines, but not so much box office or TV hits. In an effort to inject more realistic climate-related story arcs into the silver screen, NASA climate experts and Hollywood entertainment writers and producers came together last month to chat. A bus of writers and producers (from TV series such as Grimm and Curious George) dropped in on NASA’s Jet Propulsion Laboratory to hear about topics ranging from the impact of global warming on the Amazon rainforest to potentially new sources of sustainable energy involving microbes living inside termites. And in an “Entertaining Climate Change” event held in Los Angeles, producers, writers, filmmakers and artists came to listen to Dr. Jim Hansen, one of NASA’s best-known climatologists, talk about how real people are being affected by climate change now. They also learned how NASA’s suite of satellites monitors climate change around the planet and how we visualize that information.

Sassan Saatchi Writers John Vorhaus (left) and Cindy Lichtman listen to Dr. Sassan Saatchi of NASA JPL discuss the effects of climate change on forest ecosystems. Photo by Howard Pasamanick.

Spiros Skentzos Writer Spiro Skentzos listens to a presentation.

The tour was organized by Hollywood, Health and Society (HH&S), a program of the University of Southern California’s Annenberg School for Communication and Journalism based in Los Angeles. The tour was part of a new collaboration between climate.nasa.gov and the Annenberg School. HH&S hooks up entertainment industry professionals with accurate, timely information that can be used in health- and climate-related plotlines — information that is unusual, compelling and dramatic, but based on real stories about real people and places. Global instability, infectious diseases and drought are all examples of real-life storylines that are linked to climate change and that could make for thought-provoking entertainment.

The Hollywood, Health and Society group poses with a model of the Mars Rover Curiosity. The Hollywood, Health and Society group poses with a model of the Mars Rover Curiosity.

At present, TV storylines about climate change are “close to zero”, explained HH&S Director Sandra de Castro Buffington. An HH&S TV monitoring project earlier this year looked at more than 3,000 storylines used in the top 28 scripted TV shows, and found that only 24 of them — less than one percent — dealt with climate change, and most of them only peripherally.

This effort is trying to change that. While you may not see “CSI Climate”, “Attack of the Frankenstorms” or “Extreme Weather Makeover” anytime soon, hopefully TV programs and movies will soon begin to reflect the reality of climate change.

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Intuition, creativity and science
Jason Tackett has applied all three at NASA
October 17, 2012
posted by Holly Shaftel
17:00 PDT
Intuition, creativity and science
Jason Tackett stands on a mountaintop. Credit: Jason Tackett.

Jason Tackett is an analyst/programmer for the NASA satellite mission CALIPSO at NASA Langley Research Center. He is a proud member of a team of scientists who develop algorithms for this unique instrument that probes Earth’s atmosphere using pulses of laser light.

I was a musician working at a Pizza Hut before beginning college which, in my case, was synonymous with poor. Looking for a brighter future (i.e., more money), I enrolled at Kansas State University as a computer systems major. The alluring thing about this major for me was that it required creative problem solving and had the promise of big bucks. During my time there I learned about programming and computer hardware.

However, the most important thing to happen to me was a course I took in calculus. Before I started college I assumed that math wasn’t for me. As it turned out, I found mathematics very intuitive. I enjoyed the creativity and elegance that came with problem solving, much like the creativity I enjoyed playing music. My original childhood passion was astronomy, and if I enjoyed mathematics then I reasoned that I could do well studying astronomy or physics.

With this in mind, I wrapped up my associates degree in computer systems and changed majors to physics in which I earned my bachelor’s degree. I became interested in the physics of light and lasers, so I did research as an undergraduate in a high-intensity ultrafast laser facility at the James R. Macdonald Laboratory at Kansas State University. I wrote computer code for graduate researchers that helped with their experiments and also spent six months assembling a laser system.

In graduate school, atmospheric science was an attractive path because I could apply the physics I learned to important problems such as climate and climate change. When I sent out my application to graduate schools, my soon-to-be advisor at the University of Illinois at Urbana-Champaign saw that I had experience with lasers and thought that I could work with data from the new (at the time) CALIPSO satellite which uses lasers to study the atmosphere. I hadn’t thought about working with satellites before I met him, but because it sounded interesting and involved lasers and the physics of the atmosphere, I jumped on board. I spent the next two years studying CALIPSO measurements to learn how aerosol properties change near clouds – a topic of significant uncertainty in climate science.

Eventually, I was ready to look for a job and, as it happened, an opportunity opened up for an analyst with the CALIPSO science team at NASA Langley Research Center. Since I had been working with CALIPSO data for two years and my interest in optics and aerosols fit in well with the team, I was offered the job, which I eagerly accepted – and every day since I have been glad that I did.

Working for the CALIPSO satellite mission is very exciting. I get to find creative solutions to complicated problems and work with scientists to understand what data from CALIPSO is telling us about Earth’s atmosphere. In April 2010, I worked with colleagues to examine the distribution and optical properties of volcanic ash that had erupted from the Icelandic volcano Eyjafjallajökull and disrupted air traffic in Europe. NASA Headquarters asked several Earth observing satellite groups, including ours, to help identify plume location and provide guidance to air traffic controllers.

Since I have been with the CALIPSO team, my colleagues and I have also developed products for near-real time air quality monitoring and for climate modelers. I feel immense satisfaction that I work with a team that provides the high quality data that climate researchers need to solve the important issue of climate change.

It hasn’t been a straight path to get where I am today, but I am very happy with where I’ve landed.

Learn more about Earth Science Week and NASA’s Earth Explorers: http://climate.nasa.gov/esw2012/

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