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Reposted by George H. Allen

Marc Veldhoen @marcveld.bsky.social · 2d

27 things we wish we’d known when we started our PhDs

Nature’s survey of PhD candidates reveals hard-won wisdom on choosing supervisors, managing mental health and surviving academic culture.

27 things we wish we’d known when we started our PhDs

Nature - Nature’s survey of PhD candidates reveals hard-won wisdom on choosing supervisors, managing mental health and surviving academic culture.

www.nature.com

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Reposted by George H. Allen

AGU (American Geophysical Union) @agu.org · 2d

We’re on Capitol Hill with 225 Earth & space scientists — including @aas.org and @planetarysociety.bsky.social — urging Congress to reopen the government and protect NASA science. 🚀🌍

Join us: buff.ly/a3YuGgY

#ScienceIsEssential #AGU

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George H. Allen @geoallen.bsky.social · 13d

First NISAR L-band images released! They look great! www.jpl.nasa.gov/news/nasa-is...

NASA-ISRO Satellite Sends First Radar Images of Earth’s Surface

Preliminary images from the most powerful Earth radar satellite ever launched offer a tantalizing glimpse of the science the mission will be able to deliver.

www.jpl.nasa.gov

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Albert Ruhí @albertruhi.bsky.social · 15d

Looking for a postdoc, and interested in river-coastal linkages, #remote sensing, and time series analysis? Come work with us @natureatcal.bsky.social on an exciting project led by @rachelspatial.bsky.social! CC @sfs-src.bsky.social @aslo.org @cerfscience.bsky.social ‪‪@caseagrant.bsky.social‬

Rachel Carlson @rachelspatial.bsky.social · 15d

We're hiring! My lab is seeking a 2-yr Postdoc in 🌊 marine ecology + 🛰️ remote sensing. You'll work with a big team (including @albertruhi.bsky.social @cgerleinsafdi.bsky.social) to study the impacts of changing rainfall on marine freshwater plumes + coastal organisms. aprecruit.berkeley.edu/JPF05114

Postdoc Scholar - Marine ecology – ESPM The Coastal Climate Resilience Lab - MCECO - ESPM Ecosystem Sciences Div - Carlson Lab

University of California, Berkeley is hiring. Apply now!

aprecruit.berkeley.edu

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George H. Allen @geoallen.bsky.social · Aug 27

Volcanic island somewhere?

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Audrey Thellman @audreythellman.bsky.social · Jul 14

Hello freshwater friends! I’m starting a lab(!!) and recruiting 2 students to start Fall 2026 and a lab/field assistant to start this Fall 2025! Research topic is broad: rivers 🛶, ice/snow ❄️, nutrients 🍂, algae 🌱see below for more info

Please pass this along to any interested folks :)

Ad for 2 graduate student positions and and 1 lab and field assistant position at UCSB. More info go to audreythellman.weebly.com

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George H. Allen @geoallen.bsky.social · Jul 13

Correct! SWOT has a 21-day repeat orbit but most places are observed more frequently because of swath overlap

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George H. Allen @geoallen.bsky.social · Jul 12

Absolutely - we are developing a method to automatically identify and track these flood waves with SWOT. Stay tuned! In the meantime, here's the first paper on the topic if you're interested: agupubs.onlinelibrary.wiley.com/doi/full/10....

SWOT Captures Hydrologic Waves Traveling Down Rivers

Surface Water and Ocean Topography data show downstream changes in river height during a flow wave hydrologic event By removing the river's long profile, flow wave events are visualized as hydrog...

agupubs.onlinelibrary.wiley.com

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George H. Allen @geoallen.bsky.social · Jul 12

"Seen" meaning retrieved water surface elevation data over rivers while a flood wave is propagating down a river. Here are three examples of flood waves/flow waves traveling down rivers, including one in the Colorado River, TX - near the Guadalupe River:

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George H. Allen @geoallen.bsky.social · Jul 11

Flood waves like those that devastated Texas last week can be seen by the NASA #SWOT satellite. Another reason to support #NASA Earth Science

George H. Allen @geoallen.bsky.social · May 19

Hydrologists! Ever heard of a Spatial Hydrograph? Our new paper in @agu.org GRL shows that the SWOT satellite can capture spatial flow waves propagating down rivers—something previously only only observable at river gauges: doi.org/10.1029/2024...

#SWOT #hydrology #RemoteSensing #EarthObservation

Example of how the Surface Water and Ocean Topography (SWOT) satellite's water surface elevation measurements can be used to record flow wave propagation over space and generate a “spatial hydrograph.”

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AGU Hydrology H3S @agu-h3s.bsky.social · Jul 8

AGU H3S invites you to submit an abstract to our session at #AGU25 Thinking Outside the Box Plot:
Communicating Science Beyond the Paper! The session explores creative ways to communicate research. Conveners: @adischner.bsky.social
@acarneiromar.bsky.social
@gescilam.bsky.social
Cee Nell
Emily Ellis

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Reposted by George H. Allen

AGU Hydrology H3S @agu-h3s.bsky.social · Jul 8

AGU H3S invites you to contribute to our session at #AGU25 Hydrology Student, Postdoc, and
Early Career Flash Talks! This session highlights
research performed by fellow Early Career Researchers within the field of Hydrology. Conveners: Matthew Preisser and Kathryn Moore

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George H. Allen @geoallen.bsky.social · Jun 25

Hang in there and give yourself a break!

George H. Allen @geoallen.bsky.social · Jun 19

This has implications for how we calculate river and stream surface area (RSSA) at the global scale

Donut chart shows the relative contributions of each stream order to basin total river and stream surface area (RSSA)

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George H. Allen @geoallen.bsky.social · Jun 19

Scaling these widths across the Mississippi basin, we find an emergent fractal distribution of river widths (black line)

Stacked histograms of river widths colored by stream order in the Mississippi basin

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George H. Allen @geoallen.bsky.social · Jun 19

🚨New paper🚨 shows a remarkably clean relationship between river width and stream order across the US

𝑇ℎ𝑒 𝑊𝑖𝑑𝑡ℎ𝑠 𝑜𝑓 𝑅𝑖𝑣𝑒𝑟𝑠 𝑎𝑛𝑑 𝑆𝑡𝑟𝑒𝑎𝑚𝑠 𝐴𝑐𝑟𝑜𝑠𝑠 𝑆𝑝𝑎𝑡𝑖𝑎𝑙 𝑆𝑐𝑎𝑙𝑒𝑠... 🔗 doi.org/10.1029/2025...

#hydrology #geomorphology #rivers #RemoteSensing

River widths of each stream order exhibit predictable log-normal distributions.

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George H. Allen @geoallen.bsky.social · Jun 16

Using multi-scale remote sensing and fieldwork, we found that river widths of each stream order exhibit a very predictable log-normal distribution:

River widths of each stream order exhibit predictable log-normal distributions. Outer plots show distribution of river width measurements by stream order with fitted log-normal functions. Location parameter (μ) and scale parameter (σ) of log-normal fits are shown on each plot. Inner scatterplots show linear relationship between stream order (ω) and log-normal location parameter (upper scatterplot) and scale parameter (lower scatterplot).

George H. Allen @geoallen.bsky.social · Jun 3

The Washington Post also covered our paper! Here's the article with a soft paywall: wapo.st/43UuquB

Satellite measures river flow waves for the first time

The researchers assessed waves on the Colorado River in Texas, the Ocmulgee River in Georgia and the Yellowstone River in Montana.

wapo.st

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George H. Allen @geoallen.bsky.social · May 27

Hana (grad student in my group) will be doing a research internship at JPL this summer. Here she is on her first day on the job. Good luck, Hana!! 🚀🚀🚀

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George H. Allen @geoallen.bsky.social · May 21

JPL and NASA news article covering the study

NASA-French Satellite Spots Large-Scale River Waves for First Time

The SWOT mission captured the flood waves, which stretched from 47 to 166 miles long, as they traveled down rivers in Montana, Texas, and Georgia.

www.jpl.nasa.gov

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George H. Allen @geoallen.bsky.social · May 21

NASA news article on our recent study on the #SWOT satellite's ability to capture hydrologic flow waves in rivers

Link to paper: doi.org/10.1029/2024GL113875

NASA-French Satellite Spots Large-Scale River Waves for First Time - NASA

In a first, researchers from NASA and Virginia Tech used satellite data to measure the height and speed of potentially hazardous flood waves traveling down

nasa.gov

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Louise Slater @louiseslater.bsky.social · May 16

🌐 Introducing GRIT: the First Global Bifurcating River Network 🏞
developed by Michel Wortmann as part of the NERC Large Grant EvoFLOOD, in the Hydro-Climate Extremes group @oxfordgeography.bsky.social

Map of the GRIT global river network. Source: Wortmann et al. (2025), Water Resources Research.

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George H. Allen @geoallen.bsky.social · May 20

Two of the observed flow waves were caused by large rainfall events. The third flow wave was likely caused by an ice jam failure. The morphology of the flood waves appears to be dependent on the cause

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George H. Allen @geoallen.bsky.social · May 19

Three example flow waves on three rivers:

Three example flow waves shown with USGS gauge height data, reconstructed Surface Water and Ocean Topography (SWOT) water surface elevation (WSE) data, and spatial hydrographs (i.e., de-trended SWOT WSE measurements). (a) Colorado River, Texas, (b) Ocmulgee River, Georgia, and (c) Yellowstone River, Montana and North Dakota.

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George H. Allen @geoallen.bsky.social · May 19

Hydrologists! Ever heard of a Spatial Hydrograph? Our new paper in @agu.org GRL shows that the SWOT satellite can capture spatial flow waves propagating down rivers—something previously only only observable at river gauges: doi.org/10.1029/2024...

#SWOT #hydrology #RemoteSensing #EarthObservation

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