<?xml version='1.0' encoding='utf-8'?>
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>Marino Protti</dc:contributor>
  <dc:contributor>Todd Ericksen</dc:contributor>
  <dc:contributor>Julian J. Bunn</dc:contributor>
  <dc:contributor>Floribeth Vega</dc:contributor>
  <dc:contributor>Elizabeth S. Cochran</dc:contributor>
  <dc:contributor>Chris Duncan</dc:contributor>
  <dc:contributor>Jonathan Avery</dc:contributor>
  <dc:contributor>Sarah E. Minson</dc:contributor>
  <dc:contributor>Esteban J. Chaves</dc:contributor>
  <dc:contributor>Juan Carlos Baez</dc:contributor>
  <dc:contributor>James H. Foster</dc:contributor>
  <dc:contributor>Craig L. Glennie</dc:contributor>
  <dc:creator>Benjamin A. Brooks</dc:creator>
  <dc:date>2021</dc:date>
  <dc:description>&lt;p&gt;&lt;span&gt;We show that a fixed smartphone network can provide robust Earthquake Early Warning for at least two orders of magnitude less cost than scientific-grade networks. Our software and cloud-based data architecture that we have constructed for the Alerta Sismica Temprana Utilizando Teléfonos Inteligentes (ASTUTI; Earthquake Early Warning Utilizing Smartphones) network in Costa Rica is easily scaled and exported. Implementation comprises provisioning and installing modern smartphones in judicious locations. Stand-up time for regionally operational networks can be on the order of days. We evaluated a non-parametric ground-motion detection and alerting strategy that would alert the entire Costa Rican population of any event with a ground motion detection threshold of 0.55–0.65 %g at four neighboring stations. During a 6-month evaluation period ASTUTI detected and alerted on five of 13 earthquakes with M&lt;/span&gt;&lt;sub&gt;w&lt;/sub&gt;&lt;span&gt;&amp;nbsp;4.8–5.3 that caused felt Modified Mercalli Intensity shaking levels of 4.3–6. The system did not produce any false alerts and the undetected events did not produce wide-spread or significant felt shaking. System latencies were less than or similar to scientific-grade latencies. Alerts for all five detected events would have reached the capital city, San Jose, before strong&amp;nbsp;&lt;/span&gt;&lt;i&gt;S&lt;/i&gt;&lt;span&gt;-wave shaking. This would have afforded time for Drop Cover Hold On actions by most residents. Two of the five alerts were triggered by&amp;nbsp;&lt;/span&gt;&lt;i&gt;P&lt;/i&gt;&lt;span&gt;-waves suggesting that smartphone-based networks could approach the fastest theoretical EEW performance, especially with future expected improvements in smartphone sensors and processing algorithms.&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1029/2021AV000407</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>American Geophysical Union</dc:publisher>
  <dc:title>Robust earthquake early warning at a fraction of the cost: ASTUTI Costa Rica</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>