Photo: NOAA

Hurricane Harvey dumped thirteen trillion gallons of rain on southeast Texas. That water has since gathered into a massive low-salinity plume on the Texas ocean shelf. Before November, winds may carry some of this runoff to reefs in the Flower Garden Banks National Marine Sanctuary (FGBNMS), triggering mass death or disease in corals and other organisms.

Why it matters: Reefs protect shorelines and support fisheries. We know hurricanes destroy reefs through wave action, but less is known about the impacts of storm-driven runoff. As climate change increases the frequency and severity of such storms, actions to mitigate these effects will be needed.

An automated sampling buoy already observed a 10% decline in salinity near the reefs between September 28 and October 4. Scientists do not yet know the impact of this drop, but freshwater runoff was implicated in a previous mass-mortality event on the East Bank following the "Tax Day" floods in April 2016.

What's next: A team of scientists will characterize seawater conditions, microbial communities and coral and sponge health at FGBNMS this week to assess Harvey-related impacts.

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U.S. daily coronavirus cases top 50,000 for first time

Medical staff change a patient's bed sheets in the Covid-19 intensive care unit at the United Memorial Medical Center in Houston, Texas, on Tuesday. Photo: Go Nakamura/Getty Images

A record 50,655 tested positive for the novel coronavirus in the United States on Wednesday, Johns Hopkins data shows.

Of note: State governors across the country have been pausing or adjusting reopening plans in response to surging coronavirus cases across the U.S. in recent days.

Editor's note: This is a developing news story. Please check back for updates.

Updated 2 hours ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of midnight ET: 10,667,217 — Total deaths: 515,646 — Total recoveries — 5,464,367Map.
  2. U.S.: Total confirmed cases as of midnight ET: 2,685,806 — Total deaths: 128,061 — Total recoveries: 729,994 — Total tested: 32,827,359Map.
  3. Federal government: Trump says he still thinks coronavirus will "just disappear" at some point, supports another round of direct payments to Americans.
  4. Public health: Thanks to coronavirus, your home is now your gymFormer FDA chief says 500,000 Americans may be contracting coronavirus a day.
  5. States: Georgia and Arizona report record new coronavirus cases — California shuts down bars and indoor dining for most residents.
  6. 1 ⚽️ thing: 6 players test positive for coronavirus before MLS comeback tournament.
Updated 2 hours ago - Politics & Policy

Biden outraises Trump again with record $141 million June haul

Democratic presidential candidate and former Vice President Joe Biden at Philadelphia City Hall in Pennsylvania in June. Photo: Jim Watson/AFP via Getty Images

Former Vice President Joe Biden and the Democratic Party raised $141 million in June, his campaign announced on Wednesday night.

Why it matters: It's the most the presumptive Democratic presidential nominee has raised in a month. It's also more than the record $131 million President Trump's re-election campaign and the Republican National Committee raised last month.