The Sun Isn’t Responsible for Climate Change

2007-0711sun.thumbnail.jpg

I recently wrote an article for Wired Science about how there doesn’t appear to be a link between cosmic rays and global warming. Now another argument against human-created global warming has fallen to the wayside: increasing temperatures from the Sun.

It turns out energy output from the Sun has actually been decreasing over the last two decades. And during this period, temperatures across the planet have been steadily rising.

The research was published in the Royal Society’s journal Proceedings A, entitled Recent oppositely directed trends in solar
climate forcings and the global mean surface air temperature
. The report covers not only trends in solar output, but also deals with decreasing trends in cosmic rays as well.

The Sun varies on an 11-year cycle between periods of high and low activity. But above this, there’s a longer term trend. For most of the 20th century, output from the Sun was slowly and steadily rising. But in 1985, that trend reversed, with solar output slowly declining. Global temperatures here on Earth continued climbing, unaffected.

If it’s not the Sun, and it’s not cosmic rays, what’s left? Oh right… humans.

Original Source: Royal Society journal Proceedings A

Geoengineering Comes with Huge Risks

2007-0605shade.thumbnail.jpg

Over the coming decades, we’re going to learn what kind of impact global warming is going to have on planet Earth. If the impact is as severe as some scientists are predicting, countries might take drastic action to stabilize temperatures. But scientists from Concordia University and the Carnegie Institution think that tinkering with the Earth on a global scale – or geoengineering – is very bad idea, and could make the problem much worse.

In order to defend against global warming, some novel ideas have been proposed; here are a few: building a fleet of satellites to shade the planet, using mirrors to reflect light away, or releasing light-reflecting particles into the atmosphere to cool temperatures.

According to this new study, published in the June 4 Proceedings of the National Academy of Sciences, these projects could provide relief from rising temperatures, but they could worsen the situation if the projects fail or were suddenly halted. Even though temperatures would be cooled, greenhouse gas emissions would continue to rise. And if the projects failed, we could experience rates of warming 20 times what we are experiencing today.

For an analogy, let’s say you want to keep your car cool, and put shades over the windows. If you take the shades off in the heat of the day, the car will heat up much more quickly than if you let it warm up slowly in over the course of the morning. This kind of drastic temperature increase would put even more of a strain on resources, wildlife, and human populations.

Here’s what one of the researchers, Ken Caldeira, had to say:

“Many people argue that we need to prevent climate change. Others argue that we need to keep emitting greenhouse gases,” Caldeira said. “Geoengineering schemes have been proposed as a cheap fix that could let us have our cake and eat it, too. But geoengineering schemes are not well understood. Our study shows that planet-sized geoengineering means planet-sized risks.”

The researchers aren’t ruling out these kinds of megaprojects entirely, but they emphasize cutting down emissions as quickly as possible, not hoping to rely on a silver bullet.

Original Source: Carnegie Institution News Release

NASA Administrator Isn’t Sure Global Warming is a Problem

2007-532.thumbnail.jpg

I’ve got to say, I nearly fell out of my chair when I read this today. NASA Administrator Mike Griffin was interviewed on NPR about the threat of global warming. Apparently, he’s not convinced it’s a problem.

When it comes to the science on global warming, NASA is one of the good guys. They’ve got a fleet of spacecraft and aircraft analyzing every aspect of the planet. They measure ice levels, global temperatures, cloud cover, ocean levels, snow melt, rainfall patterns, dust storms, desertification and more. It’s amazing how many scientific instruments they have working on this project. They have luminaries from the scientific community working for them, like Dr. James Hansen.

And they release a hail of press releases. Just from the last week, we’ve got a story about how they detected increased snow melt in Antarctica, measuring Greenland’s glaciers, and a new release about how the Earth’s climate is approaching the point of no return.

Here’s what Griffin said on NPR:

I have no doubt that … a trend of global warming exists. I am not sure that it is fair to say that it is a problem we must wrestle with.

So he’s convinced that global warming is happening and it’s man made. But he thinks it’s arrogant for humans to decide what the perfect climate is.

… I would ask which human beings – where and when – are to be accorded the privilege of deciding that this particular climate that we have right here today, right now is the best climate for all other human beings. I think that’s a rather arrogant position for people to take.

Wow.

Sure, there’s a possibility that dramatic climate change could end up being better overall for the majority of humans on Earth, on average.

But there’s also a possibility that it’s not the case. That severe climate disruption will be terrible for a huge percentage of the population of the Earth. That the wrenching effects of change will hit the people least able to defend against it, and will suffer the most: the poor in undeveloped countries. Griffin thinks it’s okay to roll the dice. That’s it’s arrogant to not roll the dice.

If it’s okay to take that chance; if it’s arrogant to err on the side of caution, why bother investing in climate science at all? Just cut the funding, and take your chances.

NASA went into damage control mode today after Griffin’s statement, and posted a statement on its website.

“NASA is the world’s preeminent organization in the study of Earth and the conditions that contribute to climate change and global warming. The agency is responsible for collecting data that is used by the science community and policy makers as part of an ongoing discussion regarding our planet’s evolving systems. It is NASA’s responsibility to collect, analyze and release information. It is not NASA’s mission to make policy regarding possible climate change mitigation strategies. As I stated in the NPR interview, we are proud of our role and I believe we do it well.”

But this statement doesn’t really take back what Griffin said. I suspect he’s going to have an uncomfortable few weeks.

Snow Melt is on the Rise in Greenland

2007-0529greenland.thumbnail.jpg

The island of Greenland experienced more days of melting during 2006 on average than in the last 18 years, according to new NASA-funded research.

The data were gathered by the Special Sensor Microwave Imaging radiometer (SSM/I) flying aboard the Defense Meteorological Satellite Program spacecraft. It can peer through the clouds, and measure the rates of melting every day. During 2006, researchers estimated that portions of Greenland melted for an additional 10 days beyond averages.

Melting water on Greenland will impact global water levels. But the water can also slip down through cracks in glaciers, and lubricate the ice sheet. This can speed up the movement of glaciers, which eject ice into the ocean, and further accelerate sea level rise.

Original Source: NASA News Release

Sea Ice Loss Predictions Aren’t Conservative Enough

2007-0501seaice.thumbnail.jpg

The effects of global warming are already being felt worldwide, but the Earth’s poles are suffering the worst of it. Climate researchers have built a series of models to predict what impact rising temperatures will have on the amount of sea ice in the Arctic Ocean, and it appears they didn’t make these models conservative enough. Sea ice is being depleted at triple the rate that was predicted.

The research was reported in a new study by the National Center for Atmospheric Research (NCAR) and the University of Colorado’s National Snow and Ice Data Center (NSIDC). The authors compared simulations of of past climate to current observations on land and from space. The models estimated that ice would decrease at a rate of 2.5% per decade from 1953 to 2006. But the latest observations show that ice declined at an average rate of 7.8%. In other words, the decline of sea ice is currently about 30 years ahead of schedule from what researchers were originally predicting.

Several factors could have gone into the incorrect models, such as overestimating the thickness of present-day sea ice, or misunderstanding the atmospheric and oceanic circulation that transports heat to the polar regions.

Original Source: UCAR News Release

Satellites Reveal Subglacial Streams in Antarctica

View of elevation changes of an icesheet in Antarctica. Image credit: NASAAlthough it looks ancient and unchanging, the ice sheet in Antarctica is a surprisingly active place. Deep beneath the sheet’s surface, there are waterways, channels and pipes that connect various subglacial “lakes”. These channels can cause these lakes to drain away into the ocean, or transfer water from one to the other.
Continue reading “Satellites Reveal Subglacial Streams in Antarctica”

How Did Early Bacteria Survive Poisonous Oxygen?

Oxygen makes up 21% of the Earth’s atmosphere, and we need it to breathe. But early organisms would have found this environment toxic. Ancient bacteria evolved protective enzymes that prevented oxygen from damaging their DNA, but what evolutionary incentive did they have to do this? Researchers have discovered that ultraviolet light hitting the surface of glacial ice can release molecular oxygen. Bacteria colonies living near this ice would have needed to evolve this protective defense. They were then well equipped to handle the growth of atmospheric oxygen produced by other bacteria that would normally be toxic.
Continue reading “How Did Early Bacteria Survive Poisonous Oxygen?”

Biggest Ozone Hole Ever

If you’re going to Antarctica, put on your sunscreen. According to NASA and NOAA scientists, the ozone hole above the Earth’s Southern Hemisphere is the biggest on record. In late September, the new hole reached 27.5 million square km. Even through most countries banned ozone-depleting chemicals many years ago, they’re expected to continue affecting the atmosphere for decades to come.
Continue reading “Biggest Ozone Hole Ever”

Warmest World in 12,000 Years

Hot enough for you? A new NASA study has found that global temperatures are nearing their hottest level in more than 12,000 years – since the last glaciers covered large portions of the planet. In fact, global temperatures have been going up approximately 0.2° Celsius (.36° Fahrenheit) per decade for the past 30 years. In fact, global temperatures are now within one degree Celsius of the hottest temperatures measured in the last million years.
Continue reading “Warmest World in 12,000 Years”