Sunspots

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Module: Recent Climate Change Last Updated on 2011-08-04 00:00:00 Summary   This is a data-driven module designed to address key questions about the stability of the Earth’s climate in the past and the factors that drive climate change. This information is essential for students who want to study current climate change using NASA data, and interprets this in a correct historical context Goals   ·       Students will investigate how land surface and ocean surface temperatures have changed since 1840. ·       This exercise asks students to consider two contrasting interpretations of climate change over the last 2,000 years. ·       Both interpretations use a range of proxy data, but the Loehle data specifically excludes tree ring data. Investigate how the level of CO2 level in the... More »
Sunspots: Increasing the Solar Energy that Reaches Earth Last Updated on 2010-12-18 00:00:00 Periodic changes in the alignment between the sun’s rotational axis and the gravitational center of the solar system produces intense fluctuations in vertical magnetic fields of the sun. These divert heat flow from deeper layers in the sun and generate patches of fluctuating temperatures on the surface that manifest as sunspots. Although Chinese astronomers recorded the presence of sunspots as early as 28 BC, systematic counts of sunspots began with the invention of the optical telescope. These telescopes show that the number of sunspots varies with about an 11-year period as well as with some less-predictable longer cycles.                       A drawing of a sunspot in the chronicle of the 12th-century English monk John of Worcester. One might presume that solar... More »
Model Climate Sensitivity Last Updated on 2010-02-18 00:00:00 The response of climate to a perturbation such as a change in carbon dioxide concentration, or in the flux of energy from the sun, can be divided into two factors: This article is drawn from Chapter 4 of CCSP, 2008: Climate Models: An Assessment of Strengths and Limitations. A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research [Bader D.C., C. Covey, W.J. Gutowski Jr., I.M. Held, K.E. Kunkel, R.L. Miller, R.T. Tokmakian and M.H. Zhang (Authors)]. Department of Energy, Office of Biological and Environmental Research, Washington, D.C., USA, 124 pp. A Table of Contents of other articles drawn from the report is included before the references section of this article. “radiative forcing” due to the perturbation in question; and, “climate sensitivity,” characterizing... More »