May 1, 2012
The turbines that spin the generators at Southern California Edison’s San Onofre Nuclear Generating Station need steam. But the reactors at SONGS are pressurized – at roughly a ton per square inch – so the water cannot boil. Instead, hot water from the reactor is pumped through thousands of tubes. Cold water flows around those tubes, absorbs the heat of the reactor water, and boils, generating steam for the turbines. The vessels in which this takes place – the steam generators – are huge, each over twenty feet across, over 600 tons.
SCE replaced the steam generators at SONGS in 2009. The new SGs were supposed to last decades. Instead, the SGs are already wearing out. A small amount of radiation escaped the plant as a result. Both SONGS reactors are presently shut down.
In this podcast, nuclear engineer Arnie Gundersen (Fairewinds Associates) describes the SG switch-out, and how the problems may have stemmed from changes to the original design. He ends with an intriguing hypothesis as to why the design might have been changed.
March 6, 2012
Having successfully completed a major (and planned) mid-course correction, Curiosity – the Mars Science Laboratory – is now on-course for her August arrival on Mars. I spoke recently with Deputy Project Scientist Ashwin Vasavada, JPL.
March 6, 2012
Given the paucity of information coming from Tokyo Electric (TEPCO), those curious about what happened … what’s still happening … at Fukushima have had to look at the evidence themselves. I spoke with nuclear engineer Arnie Gundersen.
Aired on Soundings, 6 March 2012
November 20, 2011
The Deepwater Horizon blowout in the Gulf was only one of many offshore oil accidents. The destruction of Piper Alpha in the North Sea was another. I spoke with Brad Matsen, author of Death and Oil, on Soundings.
November 15, 2011
In the Canadian province of Alberta are rocks soaked with bitumen. It’s not crude, but more like tar. With lots of energy and water and work, bitumen can be turned into synthetic petroleum … with horrendous environmental consequences. I spoke with Andrew Nikiforuk, author of Tar Sands, on Soundings.
November 1, 2011
The most powerful – and least understood – effectors of climate are clouds.
To better understand these objects – how they both reduce and magnify the energy we get from the sun – CERES (Clouds and Earth’s Radiant Energy System) instruments now fly aboard several spacecraft, looking down on the sky.
Another CERES instrument has just launched, aboard another spacecraft. A few days before launch, I spoke with CERES PI (principle investigator), Dr. Norman Loeb, of NASA’s Langley Research Center. The conversation broadcast on Soundings, a few days after launch.
October 17, 2011
Putting a number on something gives it an aura of precision … but begs the question, “Where did that number come from?” Listeners to “Soundings” have heard me struggle to find out the origins of some of the numbers bandied about in the climate change debates. This is a short explanation for my discomfort. Aired on Steve Baker’s morning show.
September 26, 2011
Aquarius PI Gary Lagerloef explains some of the electromagnetic properties of saltwater for me. (Photograph: Kathleen Leonard)
All the sea is salt, but some parts are saltier than others. Rainfall dilutes the ocean’s waters, making them less salty. Salinity patterns thus hold clues to rainfall – key data for anyone trying to understand how rainfall patterns might be changing.
First global map of the salinity, or saltiness, of Earth’s ocean surface produced by NASA’s new Aquarius instrument
Salt affects the electromagnetic properties of water. An instrument to measure how those properties vary from place to place – and, therefore, the salinity of the ocean varies from place-to-place – was launched last June aboard the Argentine Satélite de Aplicaciones Cientificas.
The first salinity map based on Aquarius data, released in late September. I recently spoke with Aquarius Principle Investigator (PI) Gary Lagerloef about it by phone.
August 23, 2011
Earth’ atmosphere is huge – it weighs trillions of tons … and it interacts with the sun, and with the sea and the rocks of the planet, making the Earth system even larger. To try to get a handle on the atmosphere, and on climate, scientists often use computer models. I spoke with Prof. Gabrielle Hegerl of the University of Edinburgh, about some of the intricacies of climate modeling. Aired on Soundings, Aug 23, 2011.
August 9, 2011
It can be hard to observe motions in the atmosphere, since they’re usually invisible. Clouds, however, reveal some of that motion. Some very cool clouds appeared in the sky not long ago, and they revealed what was happening up there.