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Tufts Physics Dept.
Tufts Condensed Matter Physics

Letters to the Editor
Energy and Climate Change

Belmont Citizen-Herald, July 21, 2005

 It is whistling in the dark to assume that global warming won’t be a problem because “the earth is a wonderfully self-correcting mechanism” [‘Global warming debate continues,’ July 7].  No scientific principle or evidence guarantees that the earth will remain close to its present temperature.  In various epochs it has been both much colder and much warmer, and neither would be hospitable to modern humans.  The effects discussed in Daniel Baskin’s letter, along with many others, are included in modern climate models, and they’re just not enough to offset the heating caused by greenhouse gases.

 Anyone who doubts the existence of a scientific consensus on the issue should take a look at the joint statement issued last month by the National Science Academies of the United States, Canada, the UK, France, Germany, Italy, Russia, Japan, India, China and Brazil (http://nationalacademies.org/onpi/06072005.pdf)  -- the G8 countries plus the three largest producers of greenhouse gases in the developing world.  They unanimously concluded that “the threat of climate change is clear and increasing” and called for prompt action to slow and reduce the changes. 

Roger Tobin
Professor of Physics
Tufts University

Belmont Citizen-Herald, June 30, 2005

 Daniel Baskin is right, of course, that climate fluctuates naturally, and that it’s easy to be fooled by casual observations.  But he is wrong to dismiss the scientific consensus on global warming:  Human activity is producing climate change of a size and speed unprecedented in recorded history.  That conclusion is based on observational data, scientific understanding and computational capabilities far beyond anything Thomas Jefferson could have imagined.  (For details, see the report of the Intergovernmental Panel on Climate Change, http://www.grida.no/climate/ipcc_tar/ )

 By burning fossil fuels and cutting down trees, humans have greatly increased carbon dioxide in the atmosphere, and it’s climbing fast.  The increase in carbon dioxide leads, through well understood physical processes, to increased heating of the Earth.  Since fossil fuels came into wide use, average global temperatures have risen about 1 degree Celsius above a level that had remained fairly stable for at least 1000 years.  So far the effects around here have been hidden by the normal vagaries of New England weather, but in the Arctic the changes have been dramatic.  Natural sources of variation can explain only about a quarter of the temperature rise.  The rest is our doing, and it’s not stopping any time soon.  Temperatures are likely to increase by another 2-3 degrees by the year 2100, and even more thereafter.  We don’t know exactly what that warmer climate will look like, but changes of a few degrees in average temperature are no joke.  A similar change in the other direction buried Belmont under the glacier that left Cape Cod behind when it finally melted. 

 Global warming is real, it’s here, and it’s scary.  It can’t be stopped, but it can be slowed and minimized.  For the sake of future generations we need to start reducing fossil fuel use now. 

Roger Tobin
Professor of Physics
Tufts University

New York Times, October 28, 1997

To the Editor:

 If President Clinton is shocked that two-thirds of the energy used to produce electricity is "squandered" as waste heat (Week in Review, Oct. 26), he shouldn't be. And we can reduce that "waste" without repealing the laws of thermodynamics only by moving to generation methods that aren't based on heat, like solar photovoltaics and fuel cells.

 However, those who promote hydrogen use as alternative "fuel" for fuel cells are misguided. Since there are no hydrogen wells, it must be extracted from traditional fuels like natural gas, ethanol or petroleum.

 We must generate and use energy more efficiently and with fewer emissions, but our laws must comply with Nature's, because She is immune to lobbying.

Roger G. Tobin
Medford, MA 

Belmont Citizen-Herald, June 24, 1999

Background: In an article criticizing a proposal to erect a cellular phone tower, the author criticized the description of an electrical generator that is part of the project:  "The spokesman incorrectly referred to the size of the generator as 130 watts. Generator power levels are measured in KW Hrs. (Kilowatt Hours), not watts."

To the Editor:

I have no stake either way in the controversy over the proposed Cellular One tower, but as a physicist I feel compelled to clarify Paul Marzocchi's comments about the appropriate units for measuring generator capacity ("Cellular One tower deal is another case of Belmont government as usual," June 17, 1999).

Power, which is a rate of energy production or use, is measured in watts, kilowatts (thousand watts) or megawatts (million watts). I presume the Cellular One representative misspoke in saying the proposed generator would have a capacity of 130 watts, since that's barely enough for two light bulbs. More likely the proposed capacity is 130 kilowatts or 130,000 watts. The number was probably wrong, but the unit was right.

The kilowatt-hour (kWh) is a unit of energy, not power. A 100-kilowatt generator running for one hour will generate 100 kWh of energy. But that's not a measure of the capacity of the generator. A 1 kilowatt generator could produce that same amount of energy; it would just take 100 hours to do it.

Roger G. Tobin
Associate Professor of Physics
Tufts University


Science and Math Education

Physics Today, January, 2002

To the Editor:

Much of the wonderful work on K–8 science education reported by Ramon E. Lopez and Ted Schultz (Physics Today, September 2001, page 44) will be wasted, I’m afraid, unless greater emphasis is placed on training and supporting teachers.

Not long ago, in an affluent suburb known for its excellent schools, I helped my son's fourth-grade class with a unit on pulleys. The students were to measure the weight required to lift a standard load and the distance the load rose, using one, two, and three pulleys. It sounded straightforward. But the pulleys had a lot of friction and were not light compared to the load. Neither the students nor the teacher realized that the distance needed to be measured from the load's initial height, not from the floor; and no effort was made to keep the strings close to vertical. With attention to these details and judicious use of WD-40, we were able to get reasonable results, and had a good discussion about what they meant. Apparently that had never happened before. When another teacher saw the results on the blackboard, she was astonished to see patterns that actually made some sense. I can only imagine the impression of science that this unit had left on previous classes.

In other subjects, these talented and experienced teachers had no trouble improvising, identifying and solving problems on the fly, and helping students understand what they were doing. But in science they were adrift, and the kids could feel their discomfort. Teachers need help. At a minimum, every elementary school should have a full-time science specialist. In my son's school, that position had been eliminated to fund a computer room.

Roger G. Tobin
Tufts University, Medford, MA

New York Times, October 3, 1998

 To the Editor:

Re "Computers Help Math Learning, Study Finds" (news article, Sept. 30): The big problem with computers in elementary schools isn't their minimal educational value but the fact that they often replace science in the budget and curriculum. In my son's school the science room was replaced by the computer room. The Parent Teacher Association is throwing away science equipment as fervently as it raises money for more computers.

 I use computers extensively in the college physics classes I teach, so I appreciate their value in communications and advanced computation. But in elementary schools, too much is being sacrificed so that children can have all those pricey beige boxes.

Roger G. Tobin
Medford, MA Oct. 1, 1998


Other Topics

New York Times Magazine, October 19, 2003

 I suspect that even those who scoff at government services take for granted that their food and water are safe to consume; that their medicines do more good than harm; that the airplanes they travel in are safely designed, maintained and operated; that they will be warned of the next hurricane or blizzard; and even, whether they admit it or not, that they and their loved ones will not starve in the streets if they are laid low by natural disaster, financial calamity or catastrophic illness or injury. We know from bitter experience that individuals and corporations cannot or will not perform these and many other essential functions. The dedicated workers who provide these services deserve our thanks, not the derision of thoughtless citizens and opportunistic politicians.

Roger Tobin
Belmont, Mass.

(The sentence in italics was deleted by the editors from the published version.)

Boston Globe, May 30, 2000

Background: This was a response to an article about "child-free" activists who protest the benefits that they feel are lavished on people with children at the expense of those without; one letter in response argued that "People choose to have children yet expect society to subsidize their choice".

To the Editor:

Contrary to Mitchell McConnell's May 24 letter ("Missing point in debate"), it is the "child-free" activists quoted in Scot Lehigh's May 21 Focus article ("No kidding!") who are missing the point.

Societies provide support for families with children because children are a social good - not only for the private joy they bring their parents, not even only for their future economic productivity, but also in ways that transcend the cramped language of individual choice and responsibility. Children's need for care, for guidance, and for love brings us together in our shared need for community and solidarity. All societies recognize the social value of children, yet among industrialized countries the United States is among the least "child-friendly," with no paid parental leave, little access to affordable day care, and millions of children without health insurance. The minimal government and corporate benefits available to families with children are among the smallest, yet the best justified of the many subsidies (of defense contractors, mining companies, corporate agriculture, and even professional sports) that our government sees fit to enact.

Surely we can work together without rancor - those with children and those without - for a more humane society. We were all children once.

Roger G. Tobin
Linda M. Blum

New York Times, March 1, 1999

To the Editor:

I applaud the President's Information Technology Advisory Committee for reminding us that today's research is the basis of prosperity in future decades (Business Day, Feb. 24). But its recommendations, which are focused on software, telecommunications and high-end computing, are much too narrowly drawn.

History is not encouraging to those who would predict the future of innovation. The transistor emerged from fundamental research in the physics of solids, and the Internet was invented by high-energy physicists. Future breakthroughs in information technology may well come from research in optics, polymer chemistry or biology. Without a crystal ball, the best we can do is support the research and training of talented people in a wide range of fields.

Roger G. Tobin
Medford, MA, Feb. 24, 1999