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Santiago Gassó

@sangasso.bsky.social

4K followers 610 following 1.4K posts

Research on atmospheric aerosols w/satellites, models & impacts such as atmos-ocean exchange processes (SOLAS!). Atmos. polarization radiative transfer, #physics overall. Sharing and commenting on papers and sat images of (my) interest #highlatitudedust .. more

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Santiago Gassó @sangasso.bsky.social · Jun 3

🧪

Below is an old self-introduction and description of what I have fun with (professionally speaking) .

The times are quite different than when I posted this, but well, we are still here, chugging along and hoping for the best.

Santiago Gassó @sangasso.bsky.social · Dec 27

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Hello all, there are a lot of new people here so I thought of re-introducing myself. I am a Earth Observation (EO) aerosol scientist contracted to work for the only agency that has put people on the moon.
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Santiago Gassó @sangasso.bsky.social · 11h

🛰️🌬️🌍
By sunset over Patagonia today, copious amount of #highlatitudedust was being injected in the southern Atlantic region.

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Santiago Gassó @sangasso.bsky.social · 23h

@aerosolwatch.bsky.social @mparrington.bsky.social @tomgillpredicts.bsky.social

Santiago Gassó @sangasso.bsky.social · 1d

🧪🛰️🌍

Streaks of #highlatitudedust emitted in southern #Iceland.

This example illustrates an important fact about using polar sensors to detect pollution (dust in this case) and sensor spatial resolution.

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Santiago Gassó @sangasso.bsky.social · 1d

🛰️🌍🌬️
This morning #highlatitudedust in central Patagonia, copious amounts are reaching the city of Comodoro Rivadavia , where webcams show significant visibility decrease.

Santiago Gassó @sangasso.bsky.social · 1d

So a lot of work is done by satellite teams (like the ones at NASA and NOAA) to reconcile and understand these differences and make sure that different satellites are consistent in reporting properties from the same geophysical phenomenon.

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Santiago Gassó @sangasso.bsky.social · 1d

Here are the same from DT algorithm from NOAA20 sensor (native pixel 750m, aggregated at 6x6km).
In this case, there are much fewer retrievals, because each pixel is a bit too big and it captures the plume & clear sky nearby resulting in smaller observed reflectance. This results in lower AOD 5/n

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Santiago Gassó @sangasso.bsky.social · 1d

Here are the AODs derived from the DT algorithm from TERRA sensor native spatial res is 500m and product reported a 3km. (only high values are shown)

Each individual plume is well resolved and there is a clear sharp contrast in AOD between center of plume and outside.
4/n

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Santiago Gassó @sangasso.bsky.social · 1d

The issue is that frequently there is variability of the derived AOD between sensors because calibration and spatial resolution differences.

so let's look at this example in more detail... 3/n

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Santiago Gassó @sangasso.bsky.social · 1d

From the observed reflectance in the image, the operational sensors provide the aerosol optical depth (AOD) and from it , particle matter (the actual parameter of interest for AQ applications) is indirectly derived. How much is present informs decision makers on whether e.g issue AQ alerts. 2/n

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Santiago Gassó @sangasso.bsky.social · 1d

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Santiago Gassó @sangasso.bsky.social · 1d

🛰️🏭

A lot of pollution this morning in northern #Italia.

Satellite detected optical depths (a proxy for particulate concentration) from the MODIS sensor indicates high values, consistent with very high PM presence.

Reposted by Santiago Gassó

Surface Ocean - Lower Atmosphere Study (SOLAS) @solas-ipo.bsky.social · 2d

📢 Open Position Alert!
GEOMAR is hiring a Scientist/Postdoc (18 months, full time) to support the operation & expansion of the MEMENTO database within the EU project BioGeoSea 🌊🔬

🗓️ Apply by 19 Oct 2025
🔗 www.geomar.de/en/karriere/...

#JobAlert #OceanScience #Research #GEOMAR #BioGeoSea

Scientist (m/f/d) for the operation and expansion of the MEMENTO database

www.geomar.de

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Santiago Gassó @sangasso.bsky.social · 2d

that seems like a big poo patch....

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Santiago Gassó @sangasso.bsky.social · 3d

🛰️🌍
A #volcanotrack in Bristol island in the S. Atlantic. It is rare to see activity in this 🌋. Frankly I do not recall ever seeing it active (I have been making obs in this area +15yrs). It appears that activity lasted about 2 days.
Emissions remain low in altitude & wrap up w/orographic wave.

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Santiago Gassó @sangasso.bsky.social · 4d

Oh, good catch,
I was not aware of the presence of such aerosol type in será where my default has been mostly dust and sometimes mixed with dust.

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Santiago Gassó @sangasso.bsky.social · 6d

A moose?

Santiago Gassó @sangasso.bsky.social · 6d

sorry to hear that....

Santiago Gassó @sangasso.bsky.social · 6d

🛰️🌍🌊💨🧊

More #highlatitudedust yesterday this time in the northern hemisphere, in Greenland.

This MODIS Terra image does not clearly show source, probably because dust emission ended before the satellite overpass . GOES image shows that it was active during sunrise and before Terra overpass.

MODIS image - captured around 13:50 UTC - Zoom over West coast

GOES image during sunrise which suggests dust activity already present before sunrise and earlier than MODIS-Terra overpass

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Santiago Gassó @sangasso.bsky.social · 7d

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glacier in motion as seen from space , 9 year animation.

kosmi.bsky.social @kosmi.bsky.social · 8d

2015-2024

😊📹

bsky.app/profile/kosm...

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Reposted by Peter Thorne, Santiago Gassó

kosmi.bsky.social @kosmi.bsky.social · 8d

2015-2024

😊📹

bsky.app/profile/kosm...

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Santiago Gassó @sangasso.bsky.social · 8d

#ICYMI

The Associated Press @apnews.com · 8d

It's official: AOL's dial-up internet has taken its last bow.

AOL's dial up internet takes its last bow, marking the end of an era

It’s official: AOL’s dial-up internet has taken its last bow. The company confirmed it would discontinue the service on Tuesday, September 30th, citing routine evaluations of its offerings.

bit.ly

Reposted by Santiago Gassó

The Associated Press @apnews.com · 8d

It's official: AOL's dial-up internet has taken its last bow.

AOL's dial up internet takes its last bow, marking the end of an era

It’s official: AOL’s dial-up internet has taken its last bow. The company confirmed it would discontinue the service on Tuesday, September 30th, citing routine evaluations of its offerings.

bit.ly

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Santiago Gassó @sangasso.bsky.social · 8d

🧪🛰️🌍🌊🧊
Another all day cloudy in Patagonia, where lake Coluhe Huapi (next to Sarmiento in image) was active all day. This time there is no satellite view to confirm but at least there are some surface webcams that can confirm. Note there is more #highlatitudedust in suspension than yesterday.

GOES image over central Patagonia. Dust sources are obstructed by clouds.

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Santiago Gassó @sangasso.bsky.social · 8d

it worked for me before when I did the posting. But here is the direct link, just in case:
pubs.aip.org/physicstoday...

A crowdsourced database tracks US science grant cancellations

Increasing transparency and informing advocacy and litigation efforts are the main goals of the online resource, which monitors the status of funds awarded by N

pubs.aip.org

Santiago Gassó @sangasso.bsky.social · 8d

note that WV is still operational and updating images,

I think the notice refers to maintenance stuff in the background and interaction with public.

But yes, it would be desirable the WV had a worthy competitor.

Reposted by Santiago Gassó

Ocean Acidification Research Center @uaf-oarc-alaska.bsky.social · 8d

alaskabeacon.com/2025/09/29/w...

When permafrost thaw turns Arctic Alaska river red, toxicity levels rise, scientists find | Alaska Beacon

A study of the ‘rusting’ Salmon River and its tributaries in Kobuk Valley National Park suggests ecological trouble, including for salmon.

alaskabeacon.com

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Santiago Gassó @sangasso.bsky.social · 8d

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The Geography of Grant Cancellations

Interesting article in @physicstoday.bsky.social

#NSF #NIH

Physics Today @physicstoday.bsky.social · 17d

Grant cancellations by NSF this year are being tracked in a database called Grant Witness. The volunteer-run site has been used in litigation and science advocacy efforts and regularly updates grant statuses as court cases and appeals are announced.