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Mystery of the Megavolcano

Program Overview


Eruption NOVA details how a group of scientists—each pursuing his own research—pieced together the puzzle of one of the greatest natural disasters ever to occur on Earth.

The program:

  • presents ice core research that revealed high concentrations of sulfuric acid in a sample dating back 75,000 years.

  • reviews sea core research that indicated a 5° or 6° C drop in ocean temperatures 75,000 years ago.

  • profiles a scientist who began receiving chemically similar ash samples from sites separated by more than 6,500 kilometers.

  • follows that same scientist's efforts to learn more about the ash and reports on his call to researchers worldwide for ash samples.

  • tracks the subsequent detective hunt to try to identify the volcano from which the ash came.

  • notes that while one researcher sent in a matching sample from the shores of Lake Toba on Sumatra, there was no clear volcano suspect in the vicinity from which the sample was collected.

  • reveals that the volcano was determined to be underneath Lake Toba and established to be so massive that it belongs to a new class of volcanoes known as supervolcanoes.

  • recreates how magma may have accumulated for a million years in the Earth's crust underneath the lake before it erupted billions of tons of ash into the atmosphere and formed a caldera that later filled with lake water.

  • addresses the question of whether the volcanic eruption could have pushed the planet towards an ice age.

  • presents a NASA computer simulation showing how a supervolcanic eruption could activate planetary cooling.

  • speculates on what might happen if another supervolcanic eruption were to occur and notes that scientists are seeking to understand the life cycle of supervolcanoes to better predict the next eruption.

Taping Rights: Can be used up to one year after the program is taped off the air.

Teacher's Guide
Mystery of the Megavolcano