Hurricane Florence is the first storm in known Atlantic hurricane history to reach the U.S. from where it started in the North Atlantic — all others had recurved harmlessly out to sea from there.

The big picture: It's also unusually large and slow-moving, as the map above shows, and it's also approaching the coast at a nearly 90-degree angle. These 2 factors are big reasons why the storm is such a concern, and why the cable news buildup to this event is actually (somewhat) warranted.

Hurricane Florence is a Category 2 storm on the Saffir-Simpson Hurricane Scale as of Thursday afternoon.

• But that scale only measures the winds inside a storm.
• Florence will bring a storm surge consistent with a stronger hurricane because of its large wind field.
• Its slow movement also guarantees astonishing rainfall totals in inland areas.
• Wilmington, North Carolina, is forecast to break its 7-day rainfall record by more than a foot, and the state of North Carolina may break its all-time record for the wettest tropical cyclone, given the forecast for up to 40 inches of rain.

Between the lines: This storm illustrates the limits of the official rankings of hurricanes. Once the storm was "downgraded" from a Category 4 to a Category 2 on Wednesday night, Twitter lit up with concerned meteorologists worried that people in harm's way wouldn't take it seriously.

Even the National Hurricane Center got into the mix, tweeting: "Do not focus on the wind speed category of #Hurricane #Florence! Life-threatening storm surge flooding, catastrophic flash flooding and prolonged significant river flooding are still expected."

By only benchmarking a storm's winds, the Saffir-Simpson Scale ignores the deadliest aspect of a landfalling storm: water.

• Both storm surge flooding and inland freshwater flooding are a hurricane's deadliest threats by far.
• So why give the wind the most attention?

Perhaps it's because high winds used to kill more people in such storms, and the scale was developed by civil engineer Herbert Saffir and meteorologist Robert Simpson in the early 1970s.

• There have been attempts to move to other scales or tack on storm surge to the current scale. There was an effort to develop a promising metric called the Integrated Kinetic Energy, or IKE, which took into account a storm's total power. However, that failed to catch fire in the hurricane community.
• Perhaps Florence will jump-start discussions about a new scale, because talk of a storm weakening, when the surge dangers and inland flooding threats remain the same, complicates meteorologists' efforts to communicate deadly threats to the public.

The bottom line: Some of the country's most expensive hurricanes have been Category 1 or 2 storms, including Ike ($7.3 billion) and Sandy ($70 billion).

Scientists announced Wednesday they have successfully developed three key advances toward a possible pandemic flu vaccine — and it could eventually be self-administered after arriving at your doorstep via the mail, Eileen Drage O'Reilly writes.

Why it matters: Pandemics can kill huge amounts of people worldwide. The largest influenza pandemic, known as the Spanish flu, killed at least 50 million people a century ago.

Background:

• Besides the need to rapidly develop vaccines that could cover the pandemic strain (or the creation of a universal flu vaccine to cover all the possible influenza strains), medical personnel need to consider the separate challenge of how to distribute such a vaccine.

What they did: In the study, published in "Science Advances," the team took three major new steps toward a new distribution system.

They developed a short, hollow microneedle that penetrates only the top layer of the skin rather than the muscle, allowing it to be self-administered.

• "The idea of a self-administration has been very important with [the development of] a pandemic flu vaccine," study co-author Darrick Carter of the Infectious Disease Research Institute told Axios.
• Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases who was not part of the study, tells Axios the technological advances are important. "This gadget allows you to accurately give the vaccine to yourself."

They produced a noninfectious flu vaccine that would protect against the very deadly Indonesia H5N1 flu virus in an expedited process. It manufactures the vaccine in 3–4 weeks versus the normal 4-6 months needed for egg-based vaccines.

• They used a tobacco plant-based system developed by Canadian company Medicago under a DARPA program that produced 30 million doses in 30 days, Carter says.
• It's a recombinant vaccine, which means it contains virus-like particles that are not contagious and could be safely transported through the mail.
• However, Fauci points out that the vaccine itself isn't a true pandemic vaccine because no one knows if a novel H5N1 strain will pop up again.

They added an immune booster to the vaccine, called an adjuvant, which was deemed safe in their 100 person trial — making it the first one deemed safe for intradermal use.

• The adjuvant has been shown to boost the response rate of other types of vaccines, and it proved very effective here too, Carter says.

What's next: Carter says they will aim for larger human trials and the creation of the vaccine into a bandage with dissolvable microneedles.

The broad narrative on deforestation has been clear for some time — more forests are being cut down each year than are being regrown, with stark implications for biodiversity loss and climate change.

The big picture: What's less understood is what drives deforestation trends. Is it agriculture? The quest for commodities, such as palm oil and soy? Or perhaps the lucrative minerals trade?

A new study published in the journal "Science" tries to answer these questions by analyzing thousands of high-resolution satellite images in Google Earth to diagnose a cause of tree cover loss.

• They then used the information to teach a computer model to classify the most likely reasons behind forest cover loss detected worldwide via satellite between 2000 and 2015.

What they found: The main results indicate the goals set by hundreds of corporations to reduce deforestation are failing.

• According to the study by the World Resources Institute, the Sustainability Consortium and the University of Maryland, commodity-driven deforestation — where trees are cut in order to produce agricultural products — is the leading cause of tree cover loss, accounting for 27% loss during the study period.
• The study found that the rate of commodity-driven deforestation, about 19,305 square miles annually, or slightly larger than the states of Massachusetts, Connecticut and Rhode Island combined, remained constant across the 15-year period.
• Hotspots for commodity-driven deforestation are located in the Latin America and Southeast Asia.

What they're saying: "The rate of global deforestation has not declined despite the efforts and commitments made by governments, businesses, and civil society groups," Philip Curtis, consultant for The Sustainability Consortium and the study’s lead author, told Axios via email.

"Although commodity-driven deforestation rates have declined in Brazil, commodity-driven deforestation has increased in Southeast Asia and areas of Latin America beyond Brazil at approximately the same rate."

The study's authors say they hope the research helps companies determine which of their suppliers are at high-risk for causing deforestation and help them track their progress toward the sustainability commitments that they've made.

"Various types of tree cover loss give more cause for concern than others," WRI's Nancy Harris told Axios via email.

Go deeper: The researchers have made their underlying forestry data publicly available here and via the Global Forest Watch platform.

Astronaut eyes: European Astronaut Alexander Gerst snapped a unique set of images of the eye of Hurricane Florence this week.

Florence and climate: Here are the ways in which scientists say long-term, human-caused climate change is altering Hurricane Florence.

FDA and e-cigs: The FDA called for Juul Labs and four other makers of vaping devices to develop plans to keep their products away from teenagers, Marisa Fernandez writes.

Nuclear plants and Florence: How nuclear power plants prepared for Hurricane Florence, Amy Harder reports.

Interest in deepfakes: Three members of Congress asked the nation’s spymaster to investigate the national security implications of computer-generated video and audio manipulations known as "deepfakes," Kaveh Wadell writes.

CRISPR lawsuit: The long-running legal battle between the University of California and the Broad Institute of MIT and Harvard over gene editing patents ended in the Broad Institute's favor, Stat's Sharon Begely reports.

Space billboards: NASA administrator Jim Bridenstine has directed the space agency to look at selling naming rights to rockets and spacecraft, Washington Post's Christian Davenport writes.

Robotic fruit fly: Scientists have created a tiny, robotic version of a fruit fly, known as DelFly, that can reach speeds of 15 mph and turn on a dime, per Wired's Matt Simon.

Oldest drawing: "Nine red lines on a stone flake found in a South African cave may be the earliest known drawing made by Homo sapiens," according to a new study published Wednesday, Nicholas St. Fleur reports for The New York Times.

Storms in Hurricane Florence's starting location have all missed landfall in the continental U.S., largely because weather systems tend to scoop them up and dump them in the hurricane graveyard that is the far North Atlantic Ocean.

• The satellite loop shows one image per day from the GOES-16 satellite, operated by NOAA.
• With Florence, a critical role has been played by unusually strong areas of high pressure, known as "blocking highs," that have acted as atmospheric stop signs. Florence was forced to halt its northward progress and steam west-northwest, toward the Carolinas.

Between the lines: Many studies have been published tying an increase in blocking weather patterns, like the one that steered Florence into the Carolinas, to the loss of Arctic sea ice and associated changes in the temperature difference between the equator and the North Pole, but this is still a contested research area.