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Email: ollie.ballinger@st-annes.ox.ac.uk 

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Building a 3D Model of the Beirut Explosion

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Calculating High-Resolution Standardized Precipitation-Evapotranspiration Index

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This post outlines a workflow for the calculation of a high-resolution version of the Stardardized Precipitation-Evapotranspiration Index (SPEI). This is accomplished in four steps, utilizing Python, R, and JavaScript. Quantifying the precise onset, duration, and end of droughts is difficult. Most approaches have historically measured drought as a prolonged deviation from the mean rainfall in an area. The Standardized Precipitation-Evapotranspiration Index (SPEI) builds on previous approaches by incorporating temperature data to account for the amount of water lost to evaporation. This is important because in an arid climate, a six week shortage in rainfall during the summer would have a much greater impact on soil moisture than the same shortage during the winter. This is especially important for drought forecasting that accounts for anthropogenic climate change. Indices that do not incorporate temperature data will persistently underestimate drought incidence as global t
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Did Saudi Arabia Know an Attack was Coming?

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On September 14th 2019, a combination of drone and missile attacks targeted Saudi Arabia’s oil infrastructure at the Abqaiq and Khurais Aramco facilities, cutting the country’s oil production by over 50% and leading to the largest spike in the price of oil ever recorded . The attack was particularly embarrassing for Riyadh because billions of dollars' worth of air-defense systems were thwarted by drones that may have cost as little as $15,000 . A year later, the expert consensus seems to be that the attack was successful because the Saudis were caught off guard, with the element of surprise giving the assailants a decisive edge.  An open source analysis of radar interference from Saudi Arabian air defenses suggests that the Kingdom might actually have been expecting an Iranian attack on its oil infrastructure: five days before the attack, a missile defense system pointed at Iran was switched on for the first time at one of the largest refineries in the country. This analysis also
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