Climate & Environment

Speedup of Pine Island Glacier over the past several decades has made it Antarctica’s largest contributor to sea-level rise. The past speedup is largely due to grounding-line retreat in response to ocean-induced thinning that reduced ice-shelf buttressing. While speeds remained fairly steady from 2009 to late 2017, our Copernicus Sentinel 1A/B–derived velocity data show a >12% speedup over the past 3 years, coincident with a 19-km retreat of the ice shelf. We use an ice-flow model to simulate this loss, finding that accelerated calving can explain the recent speedup, independent of the grounding-line, melt-driven processes responsible for past speedups. If the ice shelf’s rapid retreat continues, it could further destabilize the glacier far sooner than would be expected due to surface- or ocean-melting processes.

Hannah Brenkert-Smith has studied the role of residents' choices in wildfire risk for two decades, with one goal being to improve mitigation programs. Her most recent work near Bailey, Colorado, concludes residents often overestimate their preparation and underestimate their risk.

Gusty winds, low humidity and dry conditions have pushed federal forecasters to issue an “extremely critical” wildfire weather warning for northwestern Colorado, the first such notice in 15 years.

The sharp drop in water levels could lead to a water shortage declaration in August.

A megadrought that's more severe than some of the worst droughts of the past 1,200 years, is underway in a 10-state region of the Southwest.

The number of earthquakes rattling the U.S. shale patch is growing exponentially as producers pump massive amounts of dirty water from their oil and gas wells back underground.

Listen now (14 min) | Hard sciences don't seem to have so many problems; why?

Death toll at 749, on course to pass high mark set in 2018, as pollution including nutrient runoff kills seagrass

Scientists from the University of Graz (Austria), Skoltech and their colleagues from the US and Germany have developed a new neural network that can reliably detect coronal holes from space-based observations. This application paves the way for more reliable space weather predictions and provides valuable information for the study of the solar activity cycle. The paper was published in the journal Astronomy & Astrophysics.

Scholars offer tips to help news outlets report accurately on scientists' work and hold the scientific community accountable for its failures.

Researchers urge newsrooms to present scientific errors and academic journal retractions as part of science's self-correction process.

The aurora borealis, or northern lights, could easily be described as Earth's greatest light show. A phenomenon that's exclusive to the higher latitudes, has had scientists in awe and wonder for centuries. The theory of how the aurora is created has been speculated but never proven, until now.

Reports of a decline in male fertility rely on flawed assumptions, a new study contends.

Air travel has been in existence for over one hundred years. Since its inception, thousands of airports runways have been built – each one of them designed site specifically, and according to landscape and natural conditions.

Street networks may be planned according to clear organizing principles or they may evolve organically through accretion, but their configurations and orientations help define a city’s spatial logic and order. Measures of entropy reveal a city’s streets’ order and disorder. Past studies have explored individual cases of orientation and entropy, but little is known about broader patterns and trends worldwide. This study examines street network orientation, configuration, and entropy in 100 cities around the world using OpenStreetMap data and OSMnx. It measures the entropy of street bearings in weighted and unweighted network models, along with each city’s typical street segment length, average circuity, average node degree, and the network’s proportions of four-way intersections and dead-ends. It also develops a new indicator of orientation-order that quantifies how a city’s street network follows the geometric ordering logic of a single grid. A cluster analysis is performed to explore similarities and differences among these study sites in multiple dimensions. Significant statistical relationships exist between city orientation-order and other indicators of spatial order, including street circuity and measures of connectedness. On average, US/Canadian study sites are far more grid-like than those elsewhere, exhibiting less entropy and circuity. These indicators, taken in concert, help reveal the extent and nuance of the grid. These methods demonstrate automatic, scalable, reproducible tools to empirically measure and visualize city spatial order, illustrating complex urban transportation system patterns and configurations around the world.

Listen now (22 min) | Estimating the size of the file drawer problem

Experiments that produce null results face a higher barrier to publication than those that yield statistically significant differences. Whether this is a problem depends on how many null but otherwise valid results might be trapped in the file drawer. Franco et al. use a Time-sharing Experiments in the Social Sciences archive of nearly 250 peer-reviewed proposals of social science experiments conducted on nationally representative samples. They find that only 10 out of 48 null results were published, whereas 56 out of 91 studies with strongly significant results made it into a journal. Science , this issue p. [1502][1] We studied publication bias in the social sciences by analyzing a known population of conducted studies—221 in total—in which there is a full accounting of what is published and unpublished. We leveraged Time-sharing Experiments in the Social Sciences (TESS), a National Science Foundation–sponsored program in which researchers propose survey-based experiments to be run on representative samples of American adults. Because TESS proposals undergo rigorous peer review, the studies in the sample all exceed a substantial quality threshold. Strong results are 40 percentage points more likely to be published than are null results and 60 percentage points more likely to be written up. We provide direct evidence of publication bias and identify the stage of research production at which publication bias occurs: Authors do not write up and submit null findings. [1]: /lookup/doi/10.1126/science.1255484

(Forthcoming Article) - Given a scarcity of journal space, what is the optimal rule for whether an empirical finding should be published? Suppose publications inform the public about a policy-relevant state. Then journals should publish extreme results, meaning ones that move beliefs sufficiently. This optimal rule may take the form of a one- or a two-sided test comparing a point estimate to the prior mean, with critical values determined by a cost-benefit analysis. Consideration of future studies may additionally justify the publication of precise null results. If one insists that standard inference remain valid, however, publication must not select on the study’s findings.

Tiny magnetometers have turned your phone into a compass, and new research shows they are sensitive to geomagnetic storms.

By Walt Hickey Welcome to the Numlock Sunday edition. This week, I spoke to James Temple of MIT Technology Review who wrote “The Climate Solution Actually Adding Millions of Tons of CO2 Into the Atmosphere” with ProPublica’s Lisa Song. Here's what I wrote about it:

The summer of 2016 was the hottest in the nation at the first and oldest national park since 770

While academic journals can take years to publish retractions, news outlets often fail to update audiences when research is deemed invalid, study finds.

Meteorologist with the National Weather Service in Boulder Kari Bowen said Sunday’s severe weather is not unusual for this time of year.