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San Francisco's 58-Story Millennium Tower Seen Sinking From Space (sfgate.com)
An anonymous reader quotes a report from SFGate: Engineers in San Francisco have tunneled underground to try and understand the sinking of the 58-story Millennium Tower. Now comes an analysis from space. The European Space Agency has released detailed data from satellite imagery that shows the skyscraper in San Francisco's financial district is continuing to sink at a steady rate -- and perhaps faster than previously known. The luxury high-rise that opened its doors in 2009 has been dubbed the Leaning Tower of San Francisco. It has sunk about 16 inches into landfill and is tilting several inches to the northwest. Engineers have estimated the building is sinking at a rate of about 1-inch per year. The Sentinel-1 twin satellites show almost double that rate based on data collected from April 2015 to September 2016. The satellite data shows the Millennium Tower sunk 40 to 45 millimeters -- or 1.6 to 1.8 inches -- over a recent one-year period and almost double that amount -- 70 to 75 mm (2.6 to 2.9 inches) -- over its 17-month observation period, said Petar Marinkovic, founder and chief scientist of PPO Labs which analyzed the satellite's radar imagery for the ESA along with Norway-based research institute Norut. The Sentinel-1 study is not focused on the Millennium Tower but is part of a larger mission by the European Space Agency tracking urban ground movement around the world, and particularly subsidence "hotspots" in Europe, said Pierre Potin, Sentinel-1 mission manager for the ESA. The ESA decided to conduct regular observations of the San Francisco Bay Area, including the Hayward Fault, since it is prone to tectonic movement and earthquakes, said Potin, who is based in Italy. Data from the satellite, which is orbiting about 400 miles (700 kilometers) from the earth's surface, was recorded every 24 days. The building's developer, Millennium Partners, insists the building is safe for occupancy and could withstand an earthquake.
Gee, let's build a concrete, 58-story tower on top of landfill. No problem!
No no, there's no condition there: "If the building isn't safe for occupancy, we'll lose a lot of money. Therefore, the building for safe for occupancy. Also earthquakes. Also dragons. Anything you want, safe."
The building itself might be able to withstand an earthquake, but the ground it's built on might not. In SF, that'd be a concern - especially since the very fact that the building sinks indicates that the ground underneath might be of the type that loses its strength when shaken.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Not sure if trolling or not. Any building built on something other than bedrock is going to settle. Even a building build on bedrock could move up or down due to seismic activity. The settling is going to happen whether the soil is warmer or not, and most of the soil under a building isn't going to heat up very quickly because the Earth is like a big heat sink. Temperature changes very slowly under ground, and seasonal variations disappear as you go deeper.
In any event, the lean is a much bigger concern than the sinking. The lean is caused by non-uniform soil, not temperature. Either there's an underground stream they didn't know about, cavities on one side they didn't know about, or other excavations are causing problems as the owners have accused.
AGW? What's the C for?
Well he just named a Goldman Sachs guy as Treasury Secretary. But yeah, Goldman Sachs is known for creating jobs and is anti-globalization. He is gonna be getting you a jerb REAL SOON now.
You mean Pence, Indiana governor, reached an agreement with a large employer in his state and offered them special incentives to stay? That is normal politics, and the only reason it was delayed until now was to serve as a talking point and trick idiots like you into giving Trump credit. See, the way this works is large employers know they are valuable and put pressure on state governments, city governments, etc. to get perks like 0% taxes, waving of pollution regulations, zoning exemptions, etc. Usually it hurts the people of the state/city long-term because the firms just make new threats as needed to keep the time-limited perks active, and environmental damage would directly harm workers and their families who do actually live nearby.
Why not blame Trump for the 1100 jobs he sent to Mexico? Carrier was moving 2100 jobs and they only kept 1000 of them here, so they lost 1100 jobs. We still don't know what incentives Pence gave them for staying, but it's entirely possible that this will be a net loss in revenue for the government. Not that I think this move is necessarily a bad thing, well paying manufacturing jobs are great to have in the country and I'm glad they were able to get them to partially stay but 1000 jobs is really a drop in the bucket for an economy that is adding 180,000 jobs per month. It's a great talking point for the Trump administration but from a practical perspective these one-off efforts aren't going to have a big impact on the economy.
Enigma
I just walked by the Tower and expected to see the foundation slab sunk below the level of the sidewalk, but nothing like that is visible, I wonder why?