Climate Archives

February 2, 2012December 24, 2015 by Jason Major

Getting to the Core of Earth’s Falling Snow

Visualization of the GPM Core Observatory and Partner Satellites. Credit: NASA

[/caption]

An international plan is unfolding that will launch satellites into orbit to study global snowfall precipitation with unprecedented detail. With the upcoming Global Precipitation Measurement (GPM) satellites, for the first time we will know when, where and how much snow falls on Earth, allowing greater understanding of energy cycles and how best to predict extreme weather.

Snow is more than just a pretty winter decoration… it’s also a very important contributor to fresh water supply in many regions around the world, especially those areas that rely on spring runoff from mountains.

The snowmelt from the Sierra Nevadas, for example, accounts for a third of the water supply for California.

But changing climate and recent drought conditions have affected how much snow the mountains receive in winter… and thus how much water is released in the spring. Unfortunately, as of now there’s no reliable way to comprehensively detect and measure falling snow from space… whether in the Sierras or the Andes or the Alps.

583801main_GPM_integration_testing_1_800-600 — Engineers are building and testing the GPM Core Observatory at Goddard Space Flight Center. (NASA/GSFC)

The GPM Core satellite, slated to launch in 2014, will change that.

“The GPM Core, with its ability to detect falling snows, it’s one of the very first times that we’ve put sensors in space to specifically look at falling snow,” said GPM Deputy Project Scientist Gail Skofronick-Jackson in an online video. “We’re at that edge where rain was fifty years ago. We’re still figuring out how to measure snow.”

And why is snow such a difficult subject to study?

“Rain tends to be spherical like drops,” says Skofronick-Jackson. “But if you’ve ever been out in a snowfall and you’ve looked at your shirt, you see the snow comes in all different forms.”

Once GPM scientists calculate all the various types of snowflake shapes, the satellite will be able to detect them from orbit.

“The GPM Core, with its additional frequencies and information on the sensors, is going to be able to provide us for the first time a lot more information about falling snow than we’ve ever done before.”

Knowing where and how much snow and rain falls globally is vital to understanding how weather and climate impact both our environment and Earth’s energy cycles, including effects on agriculture, fresh water availability, and responses to natural disasters.

Snowfall is a missing part of the puzzle, and GPM will fill those pieces in.

Find out more about the GPM program at pmm.nasa.gov/GPM.

GPM Core is currently being assembled at NASA’s Goddard Space Flight Center and scheduled to launch in 2014 on a Japanese H-IIA rocket. Initiated by NASA and the Japanese Aerospace Exploration Agency (JAXA), GPM consists of a consortium of international agencies, including the Centre National d’Études Spatiales (CNES), the Indian Space Research Organization (ISRO), the National Oceanic and Atmospheric Administration (NOAA), the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT), and others.

January 24, 2012December 24, 2015 by Nancy Atkinson

Hansen on Climate: “We need to make clear to the public what’s really going on”

Line plot of global mean land-ocean temperature index, 1880 to present, with the base period 1951-1980. The dotted black line is the annual mean and the solid red line is the five-year mean. The green bars show uncertainty estimates. Credit: Hansen et al. (2006).

[/caption]

Editor’s note: This interview is from DailyClimate.org and Climate Query is a semi-weekly feature offered by Daily Climate, presenting short Q&A’s with players large and small in the climate arena. Read other articles in the series more at Climate Query.

NASA’s chief climate scientist James E. Hansen built his career studying Earth’s atmosphere and modeling humans’ potential impacts on climate. Then he realized that laboratory work wasn’t enough. Hansen never thought his decision to study atmospheric models would lead to his arrest. But there he was in handcuffs this summer, protesting at the White House against a pipeline that would carry crude oil from Alberta’s oil sands to the Gulf of Mexico.

It wasn’t the first arrest, either. Hansen, who has directed NASA’s Goddard Institute for Space Studies for 31 years, earned the sobriquet “father of global warming” after testifying before Congress in 1988 on the dangers of global warming. He appeared again in 1989. Then he quietly returned to his work, turning aside television and media requests for the next 15 years because, as he said, “you have no time to do the science if you’re talking to the media.”

That approach changed in 2004, when he realized government climate policies worldwide failed to reflect the dangerous story his science was telling. Emerging from his lab, Hansen attacked Bush Administration officials for censuring and watering down climate findings. In 2008 he testified in British court on behalf of the “Kingsnorth Six,” a group of Greenpeace activists who successfully claimed their effort to shut down a power plant was justified under British law because it prevented the greater harm of climate change. In 2009 and 2010, Hansen was arrested protesting mountaintop-removal coal mining.

DailyClimate.org editor Douglas Fischer caught up with Hansen in December at the American Geophysical Union meeting in San Francisco, where the scientist previewed findings about impacts the world courts with its unslacked appetite for carbon-based fuels.

Question: Do you fear you have lost some of your scientific credibility by protesting at the coal plants or by becoming more of a voice in the climate debate?

Hansen: If I was not publishing papers in the peer reviewed literature, then that would be a valid criticism. But I am still publishing. I’m trying to make that science clear to the public. It’s not easy: The scientific evidence has really become very clear, and we’re not doing a very good job of communicating that.

Q: Climate policy has become less a scientific question and more a cultural marker. How can science influence those values and attitudes?

Hansen: We need to make clear to the public what’s really going on. If they just listen to politicians, they don’t understand the story because nothing is being done.

Q: Do reporters ever say, “Look, I can’t touch you as a source because you’re involved in 350.org or the coal plants or these protests”?

Hansen: The fossil fuel industry and those who prefer business as usual – they will use that. But look at my coauthors. I’ve got some of the best scientists in the world.

Q: Let’s flip the question: Do scientists ever say, “Jim, I wish I could get out there the way you are, but I’m afraid, I don’t have the support”?

Hansen: There are consequences of becoming a target. Look at the people who have been the principal targets: Phil Jones, Michael Mann, Ben Santer. Their science has been confirmed. And yet (the attacks) took a toll on them. Of course that’s going to cause other scientists not to step out.

Q: Failure to develop a climate policy isn’t a fault of just one party or one person.

Hansen: That’s right, and that’s not understood. If you say, “Democrats are the ones who favor doing something,” look at the records of the last several administrations: Emissions increased fastest during the Clinton/Gore administration. And (Democrats) proposed a policy that is not going to do anything significant. It’s designed by big banks and it favors big oil and big coal and big utilities.

Q: You’ve never liked a “cap-and-trade” approach.

Hansen: The only way you can solve the problem is with a simple, honest price on carbon. There’s no reason to bring banks into this.

Q: Where’s the clear climate message?

Hansen: Obama could’ve done it if he had started out when he had 70 percent approval and if he followed a policy like Franklin Roosevelt and had fireside chats. It’s not that difficult. It can be explained.

Q: How long can emissions increase before we risk serious impacts?

Hansen: We really should be aiming to keep CO2 no higher than about 350 parts per million and possibly somewhat less than that if we want to maintain stable ice sheets and stable shore lines and avoid many other issues. That would require starting today. We’d have to reduce CO2 emissions at six percent a year if we began next year. If we began five years ago, it would’ve been three percent. If we wait until 2020, it becomes 15 percent.

So if we’re hoping to maintain a planet that looks like the one that humanity has known, we’re out of time right now.

Interview conducted and condensed by Douglas Fischer, DailyClimate.org

January 20, 2012December 24, 2015 by Nancy Atkinson

NASA Finds 2011 is Ninth-Warmest Year on Record

While average global temperature will still fluctuate from year to year, scientists focus on the decadal trend. Nine of the 10 warmest years since 1880 have occurred since the year 2000, as the Earth has experienced sustained higher temperatures than in any decade during the 20th century. As greenhouse gas emissions and atmospheric carbon dioxide levels continue to rise, scientists expect the long-term temperature increase to continue as well. (Data source: NASA Goddard Institute for Space Studies. Image credit: NASA Earth Observatory, Robert Simmon)

[/caption]

From a NASA press release:

The global average surface temperature in 2011 was the ninth warmest since 1880, according to NASA scientists. The finding continues a trend in which nine of the 10 warmest years in the modern meteorological record have occurred since the year 2000.

NASA’s Goddard Institute for Space Studies (GISS) in New York, which monitors global surface temperatures on an ongoing basis, released an updated analysis that shows temperatures around the globe in 2011 compared to the average global temperature from the mid-20th century. The comparison shows how Earth continues to experience warmer temperatures than several decades ago. The average temperature around the globe in 2011 was 0.92 degrees F (0.51 C) warmer than the mid-20th century baseline.

“We know the planet is absorbing more energy than it is emitting,” said GISS Director James E. Hansen. “So we are continuing to see a trend toward higher temperatures. Even with the cooling effects of a strong La Niña influence and low solar activity for the past several years, 2011 was one of the 10 warmest years on record.”

The difference between 2011 and the warmest year in the GISS record (2010) is 0.22 degrees F (0.12 C). This underscores the emphasis scientists put on the long-term trend of global temperature rise. Because of the large natural variability of climate, scientists do not expect temperatures to rise consistently year after year. However, they do expect a continuing temperature rise over decades.

The first 11 years of the 21st century experienced notably higher temperatures compared to the middle and late 20th century, Hansen said. The only year from the 20th century in the top 10 warmest years on record is 1998.

Global temperatures have warmed significantly since 1880, the beginning of what scientists call the “modern record.” At this time, the coverage provided by weather stations allowed for essentially global temperature data. As greenhouse gas emissions from energy production, industry and vehicles have increased, temperatures have climbed, most notably since the late 1970s. In this animation of temperature data from 1880-2011, reds indicate temperatures higher than the average during a baseline period of 1951-1980, while blues indicate lower temperatures than the baseline average. (Data source: NASA Goddard Institute for Space Studies. Visualization credit: NASA Goddard Space Flight Center Scientific Visualization Studio)

Higher temperatures today are largely sustained by increased atmospheric concentrations of greenhouse gases, especially carbon dioxide. These gases absorb infrared radiation emitted by Earth and release that energy into the atmosphere rather than allowing it to escape to space. As their atmospheric concentration has increased, the amount of energy “trapped” by these gases has led to higher temperatures.

The carbon dioxide level in the atmosphere was about 285 parts per million in 1880, when the GISS global temperature record begins. By 1960, the average concentration had risen to about 315 parts per million. Today it exceeds 390 parts per million and continues to rise at an accelerating pace.

The temperature analysis produced at GISS is compiled from weather data from more than 1,000 meteorological stations around the world, satellite observations of sea surface temperature and Antarctic research station measurements. A publicly available computer program is used to calculate the difference between surface temperature in a given month and the average temperature for the same place during 1951 to 1980. This three-decade period functions as a baseline for the analysis.

The resulting temperature record is very close to analyses by the Met Office Hadley Centre in the United Kingdom and the National Oceanic and Atmospheric Administration’s National Climatic Data Center in Asheville, N.C.

Hansen said he expects record-breaking global average temperature in the next two to three years because solar activity is on the upswing and the next El Niño will increase tropical Pacific temperatures. The warmest years on record were 2005 and 2010, in a virtual tie.

“It’s always dangerous to make predictions about El Niño, but it’s safe to say we’ll see one in the next three years,” Hansen said. “It won’t take a very strong El Niño to push temperatures above 2010.”

For more information:

More information on the GISS temperature analysis
2010: Despite Subtle Differences, Global Temperature Records in Close Agreement (01.13.11)

January 20, 2012 by Nancy Atkinson

Desperately Seeking a Snow Day: Why So Little Snow in 2012?

Ah, for the days of Snowmageddon and Snowpocalypse back in 2010 and 2011. So far, 2012 is turning out to be a dud as far as getting a snow day or two off from work or school. Even though the Pacific Northwest in the US just got a major snowstorm, on the whole the US isn’t seeing much snowfall this winter. Why such a difference in just one year? In this ScienceCast, JPL climatologist Bill Patzert explains what’s going on.

January 3, 2012December 24, 2015 by Jason Major

A Balanced Budget on Titan

Titan and Dione seen on December 10, 2011 by the Cassini spacecraft. (NASA/JPL/SSI/J. Major)

[/caption]

It’s been said many times that the most Earthlike world in our solar system is not a planet at all, but rather Saturn’s moon Titan. At first it may not seem obvious why; being only a bit larger than the planet Mercury and coated in a thick opaque atmosphere containing methane and hydrocarbons, Titan sure doesn’t look like our home planet. But once it’s realized that this is the only moon known to even have a substantial atmosphere, and that atmosphere creates a hydrologic cycle on its surface that mimics Earth’s – complete with weather, rain, and gully-carving streams that feed liquid methane into enormous lakes – the similarities become more evident. Which, of course, is precisely why Titan continues to hold such fascination for scientists.

Now, researchers have identified yet another similarity between Saturn’s hazy moon and our own planet: Titan’s energy budget is in equilibrium, making it much more like Earth than the gas giant it orbits.

A team of researchers led by Liming Li of the Department of Earth and Atmospheric Sciences at the University of Houston in Texas has completed the first-ever investigation of the energy balance of Titan, using data acquired by telescopes and the Cassini spacecraft from 2004 to 2010.

Energy balance (or “budget”) refers to the radiation a planet or moon receives from the Sun versus what it puts out. Saturn, Jupiter and Neptune emit more energy than they receive, which indicates an internal energy source. Earth radiates about the same amount as it receives, so it is said to be in equilibrium… similar to what is now shown to be the case for Titan.

6888_16702_1 — Blue hazes hover high above thicker orange clouds over Titan's south pole (NASA/JPL/SSI)

The energy absorption and reflection rates of a planet’s – or moon’s! – atmosphere are important clues to the state of its climate and weather. Different balances of energy or changes in those balances can indicate climate change – global cooling or global warming, for instance.

Of course, this doesn’t mean Titan is a balmy world. At nearly 300 degrees below zero (F) it has an environment that even the most extreme Earth-based life would find inhospitable. Although Titan’s atmosphere is ten times thicker than Earth’s its composition is very different, permitting easy passage of infrared radiation (a.k.a. “heat”) and thus exhibits an “anti-greenhouse” effect, unlike Earth or, on the opposite end of the scale, Venus.

Still, some stable process is in place on Saturn’s moon that allows for distribution of solar energy across its surface, within its atmosphere and back out into space. With results due in from Cassini from a flyby on Jan. 2, perhaps there will soon be even more clues as to what that may be.

The team’s report was published in the AGU’s Geophysical Research Letters on December 15, 2011. Li, L., et al. (2011), The global energy balance of Titan, Geophys. Res. Lett., 38, L23201, doi:10.1029/2011GL050053.

December 13, 2011January 12, 2016 by Nancy Atkinson

Michael Mann on Climate: “There’s Still Time to Make the Right Choices”

Climate scientist Michael Mann from Penn State recently spoke at a TED event, and what he says in this video is nearly the same as in the article I wrote a year ago after hearing Mann speak — but now you can hear it from Mann himself.

The real shame here is that he needs to keep telling these same stories despite the overwhelming scientific evidence for anthropogenic climate change.

December 5, 2011December 24, 2015 by Tammy Plotner

Earth’s Magnetic Pole Reversal – Don’t “Flip Out”!

Schematic illustration of Earth's magnetic field. Credit/Copyright: Peter Reid

[/caption]

Have you heard or read stories about how Earth will some day reverse its magnetic poles? If you have, then chances are very good you’ve also heard this perfectly normal function of our planet could spell disaster. Before you buy into another “end of the world as we know it” scenario, let’s take a look at the facts.

For the record, we know that Earth’s magnetic field has changed its polarity more than once in its lifetime. For example, if you could step back in time some 800,000 years ago with a compass in your hand, you’d see the needle pointed to south – instead of north. Why? Because a compass works on magnetic fields, its needle directs you to the magnetic pole, measured as either positive or negative. The markings on the modern compass dial would be incorrect if the polarity of Earth’s magnetic fields were reversed! Like a witch hunt, many would-be prophets say natural occurrences like this might signal doom… But could their theories be correct? Unfortunately for hyperbole, the geologic and fossil records from past reversals show the answer is “No.” We’ll still be around.

Just like the Sun reversing its magnetic poles, Earthly switches are just a part of our planet’s schedule. During about the last 20 million years of our formation, Earth has settled into a pattern of switching magnetic poles about every 200,000 to 300,000 years… with a period of twice that long since our last reversal. And, it’s not a thing that happens rapidly. Magnetic pole reversal takes up to several hundred thousands of years to complete. The fields blend together and magnetic poles pop up at odd latitudes as it happens. It’s not that scary! Scientists say that Earth has reversed its magnetic field hundreds of times over the last three billion years and have sped up slightly with time.

How do we know about the impacts of magnetic pole reversal? We take a look at the deep evidence – sediment cores taken from the ocean floor. These samples are perfect fossil records which show us what direction the magnetic field was pointed in as the underwater lava emerged. These ancient flows were magnetized in the field’s direction at the time of their creation and exist on either side of the Mid-Atlantic Rift where the North American and European continental plates are moving away from each other.

“The last time that Earth’s poles flipped in a major reversal was about 780,000 years ago, in what scientists call the Brunhes-Matuyama reversal. The fossil record shows no drastic changes in plant or animal life.” says NASA’s Patrick Lynch. ” Deep ocean sediment cores from this period also indicate no changes in glacial activity, based on the amount of oxygen isotopes in the cores. This is also proof that a polarity reversal would not affect the rotation axis of Earth, as the planet’s rotation axis tilt has a significant effect on climate and glaciation and any change would be evident in the glacial record.”

MagneticPole2 — A schematic diagram of Earth's interior and the movement of magnetic north from 1900 to 1996. The outer core is the source of the geomagnetic field. Graphic Credit: Dixon Rohr

Unlike a hard-wired magnet, Earth’s polarity isn’t constant – it moves around a bit. The reason we have a magnetic field is our solid iron core surrounding by hot, fluid metal. According to computer modeling, this flow creates electric currents which spawn the magnetic fields. While it’s not possible at this point in time to measure the outer core of our planet directly, we can guess at its movement by the changes in the magnetic field. One such change has occurred for almost 200 years now… Our northern pole has been shifting even more northward. Since it was first located, the pole has shifted its place by more than 600 miles (1,100 km)! What’s more, it’s speeding up. It would seem that it’s moving almost 40 miles per year now, instead of the 10 miles per year as recorded in the early 20th century.

Don’t be fooled by those saying a magnetic pole reversal would leave us temporarily without a magnetic field, either. This is simply isn’t going to happen and we’re not going to be exposed to harmful solar activity. While our magnetic field goes through weaker and stronger phases, there is simply no evidence to be found anywhere that it has ever disappeared completely. Even if it were weakened, our atmosphere would protect us against incoming particles and we’d have more auroral displays at lower latitudes!

So, go ahead… Sleep at night. Earthly magnetic pole reversal is a normal function of our planet and when it does happen its effects will be spread out over hundreds of thousands of years – not flipped like a pancake.

Original Story Source: NASA Earth News. For Further Reading: Earth’s Inconstant Magnetic Field..

October 28, 2011January 14, 2016 by Nancy Atkinson

NASA’s New Climate and Weather Satellite Launches

The National Polar-orbiting Operational Environmental Satellite System Preparatory Project, or NPP, launched successfully on a Delta 2 rocket early today at at 5:48 a.m. EDT 09:48 GMT (or precisely at 2:48:01.828 a.m. PDT, according to NASA’s Twitter feed). The next generation satellite will measure both global climate changes and key weather variables, as well as test new technologies for future Earth observing satellites.

The spacecraft has also successfully separated and is now in orbit. The separation video is below.

Continue reading “NASA’s New Climate and Weather Satellite Launches”

October 26, 2011January 14, 2016 by Nancy Atkinson

Next Generation Climate and Weather Satellite Ready for Friday Launch

A new satellite that will test key technologies and instruments for the next generation of climate and weather-monitoring satellites is scheduled to launch on Friday, Oct. 28, 2011. The NPOESS Preparatory Project (NPP) mission has a planned liftoff from Vandenberg Air Force Base in California at 5:48 a.m. EDT/2:48 a.m. PDT.

“This is the first mission designed to provide observations for both weather forecasters and climate researchers and will provide data that is critical to climate research,” said Jim Gleason, NPP project scientist during a news briefing last week.
Continue reading “Next Generation Climate and Weather Satellite Ready for Friday Launch”

October 26, 2011December 24, 2015 by Jason Major

From the Land of Ice and Snow

Ice-coated mountaintops of Alexander Island, one of the largest islands off Antarctica. Credit: Michael Studinger/NASA.

[/caption]

Views from the window of NASA’s DC-8 reveal sweeping expanses of ice and rock as part of the ongoing 2011 Operation IceBridge survey of Antarctica’s ice cover.

Now in its third season, Operation IceBridge is a six-year-long mission to study the dynamics of the Antarctic and Arctic ice sheets. It’s the largest ever aerial survey of the polar ice and will yield valuable data on the state of Earth’s vast reservoirs of frozen water, including the land and sea underneath and how they are being affected by today’s rapidly changing climate.

6269814595_dcfb558c31_b — The ridges of the Shackleton Range cast shadows onto Antarctica's ice. Credit: Michael Studinger/NASA.

Researchers – like Michael Studinger, who took the incredible photos seen here – fly over Greenland during the months of March through May and over Antarctica in October and November. NASA’s instrument-laden DC-8 flies over these remote locations at a low altitude of about 1,500 feet, often with little or no advance weather data.

98 percent of Antarctica is covered with ice. Information obtained by Operation IceBridge will be combined with satellite data to create the most accurate models possible of Antarctic ice loss and how it will affect future sea level rise.

6280156183_cf9e274512_b — Mountains piled with snow and ice rise above the clouds on Alexander Island. Credit: Michael Studinger/NASA.

This season’s Antarctic IceBridge campaign features NASA’s DC-8, at 157 feet long the largest plane in the agency’s airborne research fleet, and will also feature the debut of the Gulfstream V (G-V) operated by the National Science Foundation and National Center for Atmospheric Research.

While the DC-8 flies at low altitudes, the G-V will fly above 30,000 feet to utilize its Land, Vegetation and Ice Sensor (LVIS), which makes detailed topographic studies of the surface.

“With IceBridge, our aim is to understand what the world’s major ice sheets could contribute to sea-level rise. To understand that you have to record how ice sheets and glaciers are changing over time.”

– Michael Studinger, IceBridge project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md.