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I wouldn't trust that graphic at the top of the article to be very accurate. It has an obvious acquisition footprint that was not resolved in processing. Those WNW-ESE stripes should've been resolved before publishing by ground-truthing the stripes using benchmarks established inside the mapped area so that the end result wouldn't suggest higher/lower subsidence along tracks than seen on parallel offset from tracks. That's just sloppy.
The striping can have multiple sources so they need to study why there is an obvious footprint and then make the appropriate corrections.
So, perhaps a dumb question, but the article mentions that 14 steps have been added to the base of the Angel of Independence monument, and the Wikipedia article mentions the same things:
> Originally, nine steps led to the base, but due to the sinking of the ground, an ongoing problem in Mexico City, fourteen more steps have been added.
So why didn't the monument itself also sink? Does it have piles going down to bedrock or something?
NISAR is the first of its kind mission, jointly developed by ISRO and NASA. It is an L and S-band, global, microwave imaging mission, with capability to acquire fully polarimetric and interferometric data.
The unique dual-band Synthetic Aperture Radar of NISAR employs advanced, novel SweepSAR technique, which provides high resolution and large swath imagery. NISAR will image the global land and ice-covered surfaces, including islands, sea-ice and selected oceans every 12 days.
NISAR mission’s primary objectives are to study land & ice deformation, land ecosystems, and oceanic regions in areas of common interest to the US and Indian science communities.
NISAR mission will help to
measure the woody biomass and its changes
track changes in the extent of active crops
understand the changes in wetlands’ extent
map Greenland’s & Antarctica’s ice sheets, dynamics of sea ice and mountain glaciers
characterize land surface deformation related to seismicity, volcanism, landslides, and subsidence & uplift associated with changes in subsurface aquifers, hydrocarbon reservoirs, etc.
Spacecraft Configuration
The Spacecraft is built around ISRO’s I-3K Structure. It carries two major Payloads viz., L & S- Band Synthetic Aperture Radar (SAR).
The S-band Radar system, data handling & high- speed downlink system, the spacecraft and the launch system are developed by ISRO. The L-band Radar system, high speed downlink system, the Solid-State Recorder, GPS receiver, the 9m Boom hoisting the 12m reflector are delivered by NASA.
Further, ISRO takes care of the satellite commanding and operations, NASA will provide the orbit maneuver plan and RADAR operations plan.
NISAR mission will be aided with ground station support of both ISRO and NASA for downloading of the acquired images, which after the necessary processing will be disseminated to the user community
The data acquired through S-band and L-band SAR from a single platform will help the scientists to understand the changes happening to Planet Earth."
> What are the practical consequences of this today
Infrastructure degradation. Think overpass collapses or metro rail lines being misaligned.
> what is being done to remedy this
Not enough. CDMX faces the issue of multiple political entities with varying power making management difficult.
A lot of the subsidence happens in informal settlements [0] due to a mixture of political populism (no one would dare demolish an informal settlement and piss off voters).
Beijing used to have a similar issue, but a mixture of hukou, mass evictions, and mass demolitions helped alleviate the issue.
We can also see it play out in other countries, that had solar water pumping for the last ten years, like afghanistan. In the end stage- its water wars with neighbours like Pakistan or Iran.
Note in particular the last one, which is a classic. Roads, buildings, and all underground infrastructure is affected. As well as anyone else who uses that groundwater, as well as future users - because come groundwater reservoirs do not recover, the compaction is permanent.
Geo-blocking by service tier. Cloudflare's "bot fight" heuristics have been flagging APAC ranges since at least 2021. Whole subnets getting painted with the same brush. Not new, just getting worse.
The way that this article is written reads like American propaganda. This is already being done, and has been done for a long time, including at the same or better temporal and spatial resolution. NISAR is genuinely cool, do I don't know why they felt the need to write this way. The new capabilities are mainly being able to do this in highly vegetated areas. In urban areas, like mexico city, this is literally 'intro to SAR' stuff.
In parts of Central Valley CA, there's been over 30 ft / 9m of subsidence from ground water extraction over several decades. (30 cm/y) Lone pipes and drains that previously sat at ground level tower over the land.
A lot of regions in the city rely on gravity to move water out of them. Floods have both increased in quantity and magnitude in recent years. If the city keeps sinking, more water will move in instead of out. Some areas of the city might become perma-flooded in a decade or two.
This is a very serious situation with no obvious solution to it.
I get that the article is primarily about the satellite capabilities, but it's rather annoying it doesn't mention what the future impact of the subsidence might be.
This is a phys.org "article". They're usually just rehashed press releases, and this one is particularly bad - it's literally just the NASA press release with the last 2 paragraphs chopped off. https://www.nasa.gov/missions/nisar/us-indian-space-mission-...
It breaks water lines which increases the water problem even faster. On one side because its expensive to fix and on the other side because small leaks lead to massive water losses you don't find fast or easy.
We ran into this managing infrastructure in a subsidence-prone area. The insidious part is that slow differential settling warps pipe joints rather than snapping them cleanly, so you get seepage that's invisible until a pressure audit flags a 15% overnight loss.
> New data from NISAR shows where Mexico City and its environs subsided by up to a few centimeters per month (shown in blue) between Oct. 25, 2025, and Jan. 17, 2026
The labels on the map were also confusing, and at first because of the relative positioning of the texts identifying the airport and the angel I thought up was East and not North, although a closer inspection made things clearer (and yes, up is North).
The gap you're pointing at is real, but impact projections for Mexico City subsidence are pretty contested — rates vary neighborhood by neighborhood. Hard to put that in a satellite press release without it being useless.
All due to some kind of game-theoretic "dilemma", like a coordination problem, collective action problem, prisoner's dilemma, principal-agent problem, tragedy of the commons.
The aquifer is the root cause. You drain it, the ground compacts, city sinks. No patch for that. They've been writing tickets against this issue for a century and still haven't fixed the underlying dependency.
Mexico City’s water stress is complicated by the fact that it sits 2240 meters above sea level on a giant plateau surrounded by mountains, so the normal solution of pumping water from somewhere else is a lot more expensive.
Excessive groundwater extraction and urban development could be reasons for this. But these are common practice in almost all of the modern world, so why is this only showing up in Mexico City.
Mexico city was built on top a dried lake. It is really fascinating stuff, I would highly recommend to look it up. Ancient farming technology, floating islands, any nerd is gonna love it.
It’s not only Mexico City. This is happening in Jakarta, the Central Valley of California, Beijing, really anywhere with excessive groundwater extraction.
It is just most people pay attention to CDMX because it is a very large 20M+ city with a lot of American and European tourists, and it is happening quickly to the point where you can see it with the naked eye.
Mexico City (Tenochtitlan) used to be a city build on a lake, partly on an island, partly on some kind of static rafts / floatting gardens (chinampas).
You can see evidence of subsidence in the rest of the developed world as well: SAR interferometry is sensitive enough to pick up the minimal amount of building movement from building Crossrail in London. It's just this article focuses on Mexico City, where it's dramatic
Knowing it's 25cm/year rather than "a lot" doesn't change much. Mexico City has been sinking since they drained the lake in the 1600s. The only remedy is stop pumping groundwater - which means finding water for 22 million people elsewhere.
Have you visited Mexico City? Your view of Mexico is likely colored by media (particularly social media) and the on-the-ground reality can be quite different.
While it’s not the best run place, it is perfectly capable of large scale infra projects and state capacity and capability is pretty well developed.
Tu entendimiento está tan equivocado que no veo ni siquiera por dónde comenzar a debatirlo, quizás si primero sacas tu cabeza de tu trasero y empiezas a conocer el mundo sería un primer buen paso.
Yeah that's "the government and people part", it's talking about the average. Of course the rich enclaves in Mexico are doing better than the average, you can find that in many places on the planet that are on average terrible places to live. But taking that into account makes it harder to crow about the ignorance of Americans, as it's so historically fun to do.
- frequent revisit, so can track even sub-monthly changes
- the L-band radar is at a wavelength (24cm) that penetrates vegetation canopy, removing a confounder from the measurement
- excellent spatial resolution that is relevant to urban scenes
The data volume is exceptionally high and required a lot of engineering effort. All radars are demanding, but this one was a new high-water mark.
(https://www.earthdata.nasa.gov/news/now-that-nisar-launched-...)