Hi, world! From here on out, I'll be posting a weekly science report/digest.
Here's the goal: stay up-to-date on current science topics in the news, as well as a chance to do some good ol' fashioned science learning. However, I am terrible when it comes to catchy titles, so I'm taking all suggestions as to a good name for this weekly contribution to the blog.
Yay for science!
If you've got a science topic you've been wondering about or you come across some interesting science in the news, please email me (firstname.lastname@example.org) or comment below and I'll incorporate into this weekly digest. And then: we will have a one-stop shop for all our science needs.
Okay, here goes... happy reading!
- What's all the hype about 1934 being the hottest year ever?
- I heard there will be a temperature rise of 6.3ºF by 2100 even if all countries enact all climate legislation proposed to date - true or false?
- The last time CO2 levels were this high was 15 million years ago - true or false?
Click "read more" to get into the science!
1. What's all the hype about 1934 being the hottest year ever?
The background here is that this became a story in 2007 when Steve McIntyre, author of the blog, www.climateaudit.org, found a Y2K bug in NASA's Goddard Institute for Space Studies (GISS) U.S. temperature data sets, which made the years 2000-2006 about 0.15ºC hotter than they really were.
GISS corrected the data set following McIntyre's critique and this correction put 1934 as the hottest recorded year in the U.S., just above 1998. Here's the corrected list of top 10 hottest years for the U.S.:
But the real point here is that this is only for the lower 48 states - it's completely different than a global average.
Some people might argue that the the U.S. data is better than the global average, because we've been keeping better temperature records than many other parts of the world. And we probably have. But LOTS of adjustments are made to the global data set to account for these potential pitfalls and a lot of effort has been put into making the global average temperatures for the last 130 years as good as they can be.
So, take-home message here is that just because the global record may be somewhat flawed, doesn't mean we should just ignore it. It still gives the best answer we have at quantifying global climate change.
And here, just for comparison's sake, are the top 10 hottest years globally, according to GISS:
And, yes, they're all in the last 12 years. If you're interested in reading more about how global temperature is measured and calculated, wikipedia has a good article on it here.
2. In the news: Temperature rise of 6.3ºF by 2100 even if all countries enact all climate legislation proposed to date
Okay, this is really depressing: A new report out by UNEP (UN Environment Programme), Climate Change 2009 Science Compendium (click here if you're a total dork and want to download the full report), which provides an update to the science that has come out since the IPCC in 2007, predicts that essentially, we're committed to at least 6ºF (3.5ºC) warming in the next century, regardless of what comes out of Copenhagen (unless it's miraculously WAY bigger emissions cuts than are being discussed right now).
The cover image on the report is pretty amazing, though:
If we take a business-usual-approach with legislation, we're looking at about 8ºF warming in the next 100 years. I think Bill McKibben of 350.org said it best, "Here's where we are: The political system is not producing at the moment a result which has anything to do with what the science is telling us."
This report also confirms that we haven't even begun to move in the right direction: the global CO2 emissions growth rate is still increasing. Global CO2 emissions increased at about 1% per year between 1990-1999, but emissions increased at 3.5% per year between 2000-2007.
This is key: it means not only are we emitting more CO2 than ever before, but the rate of growth itself is also increasing. We can't even hold to a straight line of growth. Yikes!
This increasing growth rate has put the world ahead of the worst-case IPCC scenario for CO2 emissions, also not a good thing at all. There's a good graph of this from Canadell and Raupach, 2009, which I can't get to upload right now. Stay tuned for that...
You can read the full article on the report here.
And lastly, a little paleoclimate in the news:
3. The last time CO2 levels were this high was 15 million years ago
A scientist at UCLA and others have pushed back the record of CO2 levels in the atmosphere to 20 million years ago. They measured the ratio of boron to calcium in the shells of tiny marine organisms called foraminifera (See a photo of one in the Oceans classroom module!) in marine sediment cores to infer past CO2 levels.
The last time CO2 was at a level comparable to today was 15 million years ago, when the planet was a very different place. Temperatures were 5-10ºF warmer and sea levels were 75-100 feet higher.
This is a great new piece of science to mention in the classroom presentation - that we now know CO2 hasn't been this high for 15 million years, not just the 2 million years known from ice cores.
Read the full story here.
If you've made it to the end, congratulations! Please email me any other topics you'd like to delve into in the coming weeks.