Thanks for subscribing to Axios Science. Please consider inviting your friends and colleagues to sign up. I appreciate any tips or feedback — simply reply to this email or send me a message at andrew.freedman@axios.com.

Tomorrow we launch Axios Autonomous Vehicles. It'll be worthy of your time — and written by humans. Sign up here.

Deaths in America from drug overdoses have been growing exponentially for years — with an almost eerily consistent acceleration rate of about 9% per year for the past 38 years, scientists report in a new study published today in Science, Eileen Drage O'Reilly writes.

Why it matters: Some experts tell Axios this is an urgent call to action, as the U.S. drug epidemic is more complicated and entrenched than expected.

What they did: Study author Donald Burke, who's dean of the University of Pittsburgh Graduate School of Public Health, says they examined patterns of "unintentional drug poisoning" as identified on death certificates from 1979 to 2016 in the National Vitals Statistics System.

What they found: Burke says the researchers were startled to find that drug overdose deaths doubled about every 8 years and that the problem is a composite of multiple sub-epidemics.

Threat level: While the types of drugs, users and geography changed through the years, the exponential growth rate shows Americans need to address the socioeconomic problems underpinning the crisis, Burke tells Axios.

The big question: Experts say this data will generate further research, particularly over possible deep drivers of causation. One big question is why America has had this issue for so long and with far greater intensity than other countries.

More study details:

• Almost all geographical locations (with the exception of some North Central states) have been a hotspot for drugs at one time or another.
• Heroin hotspots switched from large cities to a wider distribution.
• Fentanyl is centered in the Appalachian and Northeast regions.
• Prescription opioid hotspots initially were in Southwest and Appalachia but subsequently spread to the West, Oklahoma, Florida and New England.
• "This is a very compelling call to action," Pack says.

Go deeper: Read Eileen's full story here.

A new study reveals that the Wilkes Subglacial Basin, in the southeastern corner of the East Antarctic Ice Sheet, is far more vulnerable to even modest amounts of warming than previously thought. The study was published Wednesday in the journal Nature.

Why it matters: The fate of the Antarctic Ice Sheet represents one of the largest uncertainties in climate science, given the potential for ice melt to add feet of sea level rise around the world.

What they did: An international team of scientists drilled sediment cores off the coast of the Wilkes Subglacial Basin and analyzed its chemical composition and sediment records to sift for clues about past glacial behavior.

• Glaciers carve out and drag sediment from rocks as they flow into the sea over time, leaving a historical record of their ebb and flow buried under layers of the ocean floor.
• By unearthing this record from the deep, scientists were able to discern how this part of East Antarctica responded to warming during the late Pleistocene Interglacial periods.

What they found: The study concludes that a moderate amount of warming, on the order of 2°C, or 3.6°F, sustained for millennia, would cause significant melting of the interior ice that lies below sea level in this region, raising global sea levels by 3-4 meters, or up to 13 feet.

What they're saying: "Over the last few years, a picture has started to emerge of [the] vulnerability of low-lying areas of the East Antarctic Ice Sheet to temperatures only a few degrees warmer than today," study lead author David Wilson, a researcher at Imperial College London, tells Axios.

• Richard Alley, a climate scientist at Penn State who was not involved in the new study, tells Axios that the new study improves our knowledge of East Antarctica's fragility.
• "Oversimplifying a little, the new paper does a good job of showing that the slight extra warmth from those times led to additional transport of material eroded from the interior regions of deep basins in East Antarctica," Alley says.

Isabella Velicogna, a professor at the University of California at Irvine, tells Axios that this paper fits the theme of other studies coming out of East Antarctica, all showing it's "less stable than we have thought." She was not involved in the new study.

The graphic above shows the astounding rainfall totals in the Carolinas from Hurricane Florence. It also reveals the storm's wide scope as its rains slowly pushed northwestward, and then northeast into New England.

Why it matters: Hurricane Florence has once again proven that the category ranking of a storm doesn't match up with how much damage from rain — and inland flooding — such an event will cause.

• Some of the wettest storms in U.S. history have been relatively "weak" ones from the perspective of the Saffir-Simpson Hurricane Wind Scale.
• Both North and South Carolina recorded new maximum rainfall records.
• Since August 2017, 4 states have set all-time rainfall records: Texas, Hawaii, North Carolina and South Carolina.
• In the case of North Carolina, the new record of 35.93 inches in Elizabethtown was nearly 1 foot higher than the previous record of 24 inches, set in 1999 during Hurricane Floyd.

As was the case in Texas with Hurricane Harvey, the rainfall totals in the Carolinas had a recurrence interval of less than 1 in 1,000 years, or a probability of occurring in any given year of 0.1%. However, given that the climate is warming due to human activities, thereby adding more fuel to storms in the form of water vapor, such extreme rainfall events are becoming more frequent and intense.

The impact: The flooding cut off towns, spilled hazardous substances from hog farms and threatened to do so from coal ash facilities. It also slowly claimed more than 2 dozen lives since the storm made landfall on Sept. 14.

Go deeper:

• The ties between Hurricane Florence and Climate Change
• Florence was another 1,000-year rain event. Is this the new normal as the planet warms? (Washington Post)

Elephant poaching cartels: Forensic scientists used novel DNA detective work to identify elephant poaching cartels. This work could aid in prosecuting wildlife traffickers.

"First Light" images: NASA's new Transiting Exoplanet Survey Satellite (TESS) has sent back its first images from space, and they're beautiful.

TB "Crisis:" The World Health Organization found that while mortality has dropped from tuberculosis infections, nations must still accelerate their response to what remains "the world's deadliest disease," Eileen writes.

GMOs and climate: Bill Gates says GMO's can help farmers fend off the effects of climate change on their crops, Amy Harder writes.

Building Boom and Nature: Hurricane Florence illustrates our increasingly perilous position in states where the population is growing faster than our capacity to be resilient in the face of disasters.

How AI will change your thinking: AI may provide us with intelligence boost by coordinating still-unsurpassed human brainpower and correcting some of the errors inherent how we think, Kaveh Waddell writes.

Sexual harassment policy: The National Science Foundation unveiled new rules for reporting harassment by grant recipients, writes Nature's Alexandra Witze. The rule will apply to all new grants and any extensions to existing grants.

Racial disparities: A ProPublica analysis of newly released FDA data found that "in trials for 24 of the 31 cancer drugs approved since 2015, fewer than 5% of the patients were black. African-Americans make up 13.4% of the U.S. population."

Genetic research: Only a sliver of the human genome has been studied, despite nearly the entire genome being known. This may be because of incentives that keep scientists from exploring the unknown, Carl Zimmer reports for The New York Times.

The European Space Agency's Mars Express spacecraft took a series of images of tectonic activity that took place long ago — on the order of 10 million years — of a fault system near the planet's equator.

The big picture: Specifically, the image above shows part of the Cerberus Fossae system on the Elysium Planitia region of Mars.

Fossae in Latin means "ditches" or "trenches," according to ESA, and these particular ones can be found in a region that is 620 miles from northwest to southeast.

The details: "They cut through impact craters and hills along the way, as well as 10 million year old volcanic plains, indicating the relative youth of their formation," ESA writes in a press release. The fossae are areas where faults have pulled the upper layers of Mars' surface apart, and they occasionally stretch nearly a mile wide.

"They could be linked to injections of lava at depth deforming the surface above, perhaps originating from the trio of volcanoes that are located to the northwest," ESA says.

The round pits to the right of the image are areas where the surface is sinking.

By the numbers: Mars Express has been in orbit for 15 years and has taken more than 40,000 images of the red planet and its two moons.