Monthly Archives: December 2011

When More Is More

In science, less isn’t more; more is more.

That basic premise is supported by a recent report from Lawrence Livermore National Laboratory: Separating signal and noise in climate warming.  Earth’s overall temperature is affected by natural processes, such as La Niña and El Niño, as well as by human factors.

From 1999 to 2008, Earth’s temperature was fairly steady, coming after the steady rise in temperature that occurred from the late 1980s.  What happened in that 10 year period?  Probably noise from natural phenomena, conclude scientists at LLNL.

“Looking at a single, noisy 10-year period is cherry picking, and does not provide reliable information about the presence or absence of human effects on climate,” said Benjamin Santer, a climate scientist and lead author on an article in the Nov. 17 online edition of the Journal of Geophysical Research (Atmospheres).

The solution?  Look at longer time periods to see past the natural noisy fluctuations in Earth’s temperature data.  After looking at all of the data, scientists concluded that temperature records must be at least 17 years long to see the human-caused warming amidst the natural fluctuations.  More data leads to more accurate conclusions.

Explore the hows of climate change in the High-Adventure Science climate investigation.

Absolute Certainty Is Not Scientific

That’s the title of an editorial by Daniel Botkin, president of the Center for the Study of the Environment and professor emeritus at the University of California, in today’s Wall Street Journal.

With the ongoing polarization of science in today’s political environment, it’s more important than ever to remember that science is filled with uncertainty.  Everything that scientists know about how the world works has been discovered by observation and experimentation.  None of us were around at the very beginning, so we can never be absolutely certain about how the world works, though we can be very certain that we understand how it works.

You can’t prove anything to be true in science.  This seems unintuitive to many people, including many of my former students, who used to insist that they had proven their point because the data supported their hypotheses.  But since we will never be absolutely certain about how the world works, we can never prove that any particular hypothesis or theory is absolutely true.  That’s why good scientists design experiments to disprove their hypotheses.  While you can’t prove anything to be true, you can prove things to be false.

So good scientists are forever questioning their assumptions, looking for evidence that their hypotheses and theories are wrong, open to the idea that they may have misinterpreted the data.  It’s vitally important for science teachers to remind their students to have this kind of healthy skepticism; scientific progress cannot easily proceed if people entrench themselves into opposing camps without regard for the data.

This is something that the High-Adventure Science investigations aim to do–immerse students in the data about climate change, finding extraterrestrial life, and freshwater resources–without making all-or-nothing judgements about the current state of the science.

“If you think that science is certain–well that’s just an error on your part.” ~Richard Feynman