Amy Hessl
West Virginia University, WV·Earth & Environmental Science
Storms of energetic particles from the sun threaten satellites, space stations and astronauts. Instruments have only recorded these events for a few decades.
- Fields
Earth & Environmental Science
Plant Science & Agriculture
Ecology & Evolution
- Topics
dendrochronology
tree rings
radiocarbon
- Grants
- 1 known grant, through Sep 2027
What they work on
- Measure the age of carbon that living trees allocate to new wood at three sites, comparing evergreen conifers, deciduous conifers and deciduous angiosperms.
- Build new tree-ring carbon-14 records of the 663 BCE, 774 CE and 993 CE radiocarbon spikes from the same sites, to use as natural pulse-labeling experiments.
- Test how tree physiology and geomagnetic latitude affect estimates of the timing, duration, magnitude and solar phase of past solar particle events, using a Bayesian model and the global tree-ring dataset.
More about the research
Tree rings and ice cores, however, suggest that rare past events were about 50 times more severe than anything seen in modern records. When such a storm strikes, it produces a spike of radiocarbon (carbon-14) in the atmosphere, and trees lock that spike into their annual growth rings. Reading these spikes precisely could set an upper limit on how extreme solar events can get. But the record is blurred by uncertainty about how old the carbon in each ring really is, because trees store sugars and starches (non-structural carbohydrates) before building wood. The record may also vary with latitude.
Why it matters
A reliable history of extreme solar particle storms could improve space-weather forecasting and risk assessment. It would set an upper limit on the most severe events that satellites, space stations and human space missions must be designed to withstand. Correcting tree-ring records for tree physiology and latitude may also make radiocarbon archives more precise for studying past solar activity.
Known grants
From NIH and NSF research grants. Labs often have other funding we can't see.
Closest labs
Xinlin Li
University of Colorado Boulder, CO·Astronomy & Astrophysics
Analyze more than 12 solar energetic particle events seen by the REPTile-2 CubeSat detector, combined with NOAA/POES, MetOp and ground riometer data, to measure how storms shift the latitudes where particles reach the polar atmosphere.
Karen King
University of Tennessee-Knoxville, TN·Earth & Environmental Science·Early-career
Use quantitative wood anatomy, measurements of individual wood cells in tree rings, to build high-resolution temperature and precipitation records over the last millennium across temperate North America.
Veronica Bindi
University of Hawaii at Manoa, HI·Physics
Operate and maintain the Simpson Neutron Monitor Network, ground detectors counting cosmic-ray secondaries, and deliver real-time count rates plus archived and high-resolution datasets to the research community.
The school
West Virginia University: 15 labs on PI Pages, $259M a year on research, 201 research doctorates a year.
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