Question

When these phenomena are induced by a co-rotating interaction region, HILDCAA (“hild-kah”) events can occur during their recovery phase. The SWPC forecasts these phenomena using data from DSCOVR (“discover”), which replaced ACE (“ace”) in 2015. (-5[1])These phenomena’s Ap (“A-P”) index is an eight-point running average of their Kp index, (10[1])which is a quasi-logarithmic value (-5[1])reported every three hours. Some of these phenomena are preceded by so-called “sudden commencements.” During the main phase of these phenomena, the Dst (“D-S-T”) index takes on large, negative (10[1])values. (-5[1])These phenomena occur when the ring current is intensified past (-5[1])a threshold (-5[1])value. (10[1]-5[1])Detections of coronal mass ejections (-5[2])are used to forecast these phenomena and the resulting disruption to GPS (-5[2])satellites (-5[1])and (-5[1])power (-5[1])grids. (10[1]-5[1])For 10 points, auroras (-5[1])at unusual latitudes are caused by what phenomena (-5[1])in which the solar wind disturbs the magnetosphere? (10[2]0[1])■END■ (10[1]0[8])

ANSWER: geomagnetic storms [prompt on storms; until “solar wind” is read, prompt on solar particle events, SPEs, solar energetic particle events, SEP events, solar radiation storms, or solar storms by asking “what phenomena are associated with that event in this case?”; reject “substorms” or “geomagnetic reversals” or “geomagnetic excursion(s)”]
<Other Science>
= Average correct buzz position

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Summary

2023 ACF Nationals04/22/2023Y2133%0%76%103.00

Buzzes

PlayerTeamOpponentBuzz PositionValue
Justin DuffyHarvard AVanderbilt A31-5
Alex LiGeorgia Tech ADuke A4410
Ethan AshbrookMinnesota APenn A49-5
Geoffrey ChenCornell AUC Berkeley A7710
Stevie MillerMaryland AHouston A78-5
Matthew LehmannWUSTL AIndiana A88-5
Kevin ParkClaremont ABrown A90-5
Dennis ReppenChicago CMichigan A91-5
June YinWUSTL BYale A9110
Robert WangPenn State AIllinois A96-5
Matthew SiffYale BColumbia B96-5
Clark SmithOhio State ARutgers B108-5
Matt JacksonChicago ARutgers A108-5
Ian ChowToronto ASouth Carolina A109-5
Ricky LiMIT AFlorida B110-5
Morgan BozemanMinnesota BCornell B111-5
Geoffrey WuColumbia AMcGill A11210
Maximillian NieburJohns Hopkins ANorth Carolina A112-5
Enoch YuenImperial AIowa State A116-5
Eric WolfsbergStanford AGeorgia Tech B124-5
Jason HongBrown AClaremont A13210
Jim FanNorth Carolina AJohns Hopkins A13210
Yash MandaviaIllinois APenn State A1320
Richard NiuCornell BMinnesota B13310
Todd MaslykMichigan AChicago C1330
Benjamin McAvoy-BickfordPenn AMinnesota A1330
Joelle SmartRutgers AChicago A1330
S. A. ShenoyGeorgia Tech BStanford A1330
Noah ChenColumbia BYale B1330
Mateo Javier AcostaFlorida BMIT A1330
Ben DahlPurdue AFlorida A1330
Tracy MirkinFlorida APurdue A1330