October 28, 2013

Energy Transition: Moving Into a Better Future

On 20 October, 2013 my brother, one of the most important men in my life, was married in a beautiful outdoor ceremony, surrounded by the love of family and friends and by the peace of nature, the whole suffused in brilliant sunshine. His bride, my new sister, was even more radiant than she usually is.

Photo Jason Hutchens

Neither of them are extremely young. They have each seen quite a bit of the world, sometimes on their own, sometimes in a relationship, so far transitory. They have known the advantages to being unattached. There is a certain kind of freedom that you enjoy if you only have to take care of yourself and no-one else.

Like many of us, these two people have decided to give up that freedom, in exchange for a formal and lasting connection, made of their own free will, in a leap of faith that their life together will be better than the separate lives they are leaving behind.

October 25, 2013

Review: Hyundai Elantra / Avante

For the occasion of my brother's wedding, my family completely ruined our carbon footprint for this year. Because this is the middle of the school year, we flew over for just a few days, and we rented a car so that my dad could come with us everywhere.

The rental car was a Hyundai Elantra, a four-door sedan. I was offered an upgrade at pickup time, but declined, figuring you shouldn't drive a rental car that's too much larger than the one you drive daily. I hear this car is popular with rental car agencies because of its good maintenance record.

The Elantra falls in the "Economy" rental bracket, which means it carried five of us comfortably. Our luggage rattled around in the large trunk, which could easily accomodate both our cellos. There were a few blind spots that were larger than I would like, particularly the bar between the front windshield and the side windows.

The Elantra had a slight drive-by-wire feel to the handling, but it wasn't overwhelming. Its 1.8L, 148HP engine was completely up to the job of moving the car even when fully loaded (five people plus luggage), even for quick insertions in rush-hour traffic.

October 11, 2013

The Warmest Day of Your Life - So Far

Okay, try this with me: Bring up the memory of the hottest day in your life. Picture it: Where were you that day? What were you doing? Who was with you? How did you cope with the heat?

I'll start.

The time was August 1988, a few weeks before the start of the academic year. The Northeast was gripped by a ten-day heat wave. I went to Boston's Logan Airport, to meet my then-boyfriend, who had decided to come to the US to go back to school.

He emerged from immigration and customs wearing a thin layer of perspiration. I could tell it wasn't my lovely presence that caused him to pant slightly.

"It's so hot!" was almost the first thing he said.

"Hot?" I said, "It's cool in here; this terminal has air-conditioning."

"This is air-conditioned?" he yelped.

October 8, 2013

Radiative Forcing and Global Warming Potential

Sometimes science seems to use English words, but on closer inspection you find that the meaning of those words are not what you're used to.

"Positive Feedback" is a good example. At school, or at work, positive feedback is when you're complimented for a job done well. In the context of climate science, positive feedback often denotes a vicious cycle or self-reinforcing global warming, as in when waming leads to melting of permafrost, which releases methane (a powerful greenhouse gas), which in turn leads to further warming.

"Stampede Loop" by John Trevithick, a great example of a positive feedback loop.

I could think of a bunch of racier examples, but this is a general-audience blog, so I will refrain. Suffice it to say that sometimes scientists, with a straight face, will bandy about terms that in an ordinary non-scientific conversation would make you blush.

But back to global warming. The following are notes on my reading up about several terms that have been used a lot - but I realised I didn't quite understand. I learned that the fearfully named "radiative forcing" is simply the imbalance on the planet's energy balance sheet. That the term "global warming potential" is fraught with details, caveats and snags that nobody ever talks about. And I found out the reason for why people talk of the temperature rise associated with a "doubling of the CO2 concentration", rather than an increase by some amount.

October 7, 2013

October 5, 2013

Of Electric Vehicles and the Intergluteal Cleft

In case you were wondering, the intergluteal cleft is popularly known as the "butt crack": that which becomes visible when you wear low-hung jeans and do anything but stand up straight.

Such jeans are also known as "plumbers' pants" not because plumbers are excessively fond of them compared to those of other professions, but because when they work under your sink they display the defining property of these sagging pants.

 photo Butt_Crack.jpg

Urban legend has it that wearing sagging pants originated in the US prison system, and were popularised by hip-hop artists in the 1990s, who turned the sagging pants into a fashion must-have. At first, really not that many people wore their pants that way. But now sagging pants have spread into the mainstream to the point that jeans for women are "low-rise" by default and you have to work hard to find a pair of jeans that hug your hips instead of miraculously hanging off them, seemingly defying gravity.

So now you know. But not to worry, this is a serious post. Electric cars are not to be the butt of any jokes cracked by me.

Electric cars, in fact, are very serious business. Over the past few years their sales have soared, and the discussion has finally shifted from range anxiety to the installation of charging points in this and that city.

October 2, 2013

Natural Gas: Bridge Fuel or Dead End?

[NOTE added 27 February 2014: There is NO scientific evidence that a positive feedback has kicked in. While methane levels are high (and increasing), they would have to be much, much higher to trigger "runaway global warming". Scott Johnson de-bunks the claims of a "methane emergency" (and the subsequent extinction of the human race by 2035) in this well-argued post].


A while ago, I looked into cars that run on compressed natural gas. Natural gas is cheap. It has been touted as a "clean" source of energy - anyway cleaner than coal. The burning of natural gas does not release soot particles that post a health problem; in addition, generating energy from natural gas releases less carbon dioxide, a greenhouse gas that causes global warming.

At least, that's the argument given by proponents of hydraulic fracturing, or "fracking" of gas-containing shale. But methane (CH4), the main component of natural gas, is itself a greenhouse gas, and one that is much more potent than carbon dioxide. Its global warming potential is usually quoted as GWP=25.

What that means is that methane is 25 times more effective at trapping heat than carbon dioxide, over a period of 100 years after its release into the atmosphere: GWP(methane, 100yr) = 25.

So, if methane is really to be a "clean" (meaning low-GWP) source of energy, there had better be no leaks: not around the rigs where the fracking happens, not in the pipelines that take that natural gas to power plants and homes.

But methane does leak.

This is not the ideal world, and as any homeowner knows, sooner or later some pipe in the house will leak.

The leaks around a fracking field can be as high as 9% of the recovered methane. That's enough to make natural gas a much less "clean" fuel, in the context of global warming, than coal.

Pipelines to users, exposed as they are to varying temperatures, vibrations, aging, and other realities, leak also. A team of scientists have taken a natural gas sniffer along roads all over Boston, MA, looking for any leaks. The picture is not pretty.

Image by Kaiguang Zhao of Duke University

In the image, the height of the spikes indicate the methane concentration at that location. Yellow indicates a concentration higher than 2.5 parts per million. In Cambridge, you can see Harvard and MIT light up.