Earthquake felt in NE US.

"Earthquake rattles Northeastern U.S., shakes felt in New York City, New Jersey, Connecticut" https://www.yahoo.com/news/earthquake-rattles-northeastern-us-shakes-felt-in-new-york-city-new-jersey-connecticut-144832095.html?guccounter=1

Originally Posted by: Chunky Pea 

how does 4.8 compare to what we have had over here?

There's been a magnitude 7 quake in California and a tsunami warning has been issued
https://www.bbc.co.uk/news/articles/ce3lyxgez5xo 

More info here: https://earthquake.usgs.gov/earthquakes/eventpage/us7000nw7b/executive

Originally Posted by: Gandalf The White 

The warning has now been cancelled on the latest update.

Originally Posted by: doctormog 

Hi Michael, yes, I noticed that but didn't want to edit my post a second time!

Still potentially quite serious in terms of damage.

Originally Posted by: Gandalf The White 

Is it me or are these tsunami warnings more often than not false alarms? Do some improvements need to be made to the models that trigger the warning or is it a case of ‘earthquake off the coast, let’s trigger the warning just to be safe’?
Asking for a friend.

Originally Posted by: nsrobins 

The latter, I think, especially in this litigious age. You can imagine the reaction if no warning was issued and then a tsunami hit.

Originally Posted by: Gandalf The White 

Good points but I’m interested in the accuracy of the tsunami modelling. There has to be a bit more to it than ‘it’s an earthquake, evacuate now’? The algorithms that model wave propagation etc might need a little refining given how often the warnings are issued then cancelled shortly afterwards - in the meantime thousands have started to move, industry closes, etc etc.

Originally Posted by: nsrobins 

Admittedly with my very limited knowledge, I would have assumed that the factors would be the strength of the earthquake, the depth below the surface and the depth of water.  Also, doesn’t the type of earthquake matter?  From past ones I thought tsunamis were the result of a sudden raising or collapsing of the sea floor: if that’s the case, is that predictable?

Originally Posted by: Gandalf The White 

HArd to believe its 20 years since the Boxing day Tsunami.  Remember it like yesterday and the weeks that followed. Watching the news in disbelief. The first natural disaster caught on first gen camera phones as well

Originally Posted by: The Beast from the East 

Yes, those 20 years have gone so quickly.
Having family in Indonesia personally affected by the disaster, it is something we always remember. We were there in September, and sitting on the beach watching the fantastic sunset over the Indian Ocean, it was hard to imagine the power that can be unleashed in seconds from under the sea.
We hear the stories of tourists who were caught up in this, and the understandable struggles they have had returning home after losing family members, But for the communities there near the epicentre, the rebuilding and regrowth that has taken place is amazing, and if not for the memorials it would be difficult to know such a huge disaster had happened. The ability of these communities to recover from such a catastrophe is remarkable. Wherever you go in Indonesia, you are never far from an active volcano and earthquakes, although thankfully mostly small, happen regularly. The locals accept these hazards and live their lives not in fear but in full knowledge of the power that is always nearby.

Originally Posted by: Steve