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EasyPhil
06-01-2002, 12:16 PM
Does lightning strike buildings during a thunderstorm? Is there usually damage? What types of things attract lightning other than trees?

friedo
06-01-2002, 12:36 PM
All skyscrapers have very good grounding systems in place in case of lightning strikes. So damage is usually minimal.

bbeaty
06-01-2002, 12:45 PM
Originally posted by EasyPhil
Does lightning strike buildings during a thunderstorm?

Yep. Most lightning stays high, within the storm, but when lightning hits the ground, it tends to strike anything that sticks up (trees and buildings, etc.)

Is there usually damage?

Yes, if there were no lightning protection devices. Most lightning doesn't have the sustained current needed to cause fires, so the damage tends to be to electronics and appliances. If lightning strikes an internally damp object such as a tree, it can cause a violent explosion via expanding steam.

What types of things attract lightning other than trees?

People on golf courses? :)

Seriously, anything that sticks up out of the ground can attract lightning. The "attraction" is not actually attraction. Instead, whenever a lightning bolt approaches from above, objects on the ground will launch their own streamers of conductive plasma upwards. These streamers are themselves lightning bolts. The first streamer to touch the incoming lightning will become part of the main lightning bolt. Since tall objects have a head start with these streamers, usually the streamer from a tall object will win the race. An insulating object won't launch a streamer, but an object with even a slight amount of conductivity will.


A great book on such things is:

ALL ABOUT LIGHTNING
http://www.amazon.com/exec/obidos/ASIN/048625237X/

by Dr. Martin Uman, U. of Florida
http://www.ece.ufl.edu/profiles/pfelma.html#umamar

Lightning FAQs
http://www.nofc.forestry.ca/~kanderso/ltgfaq.html
http://www.nssl.noaa.gov/edu/ltg/
http://www.nssl.noaa.gov/edu/storm/
http://www.lightningtech.com/d~ta/faq2.html
http://tlpinc.com/MOREINFO/lightning_faq.htm
http://www.lightningstorm.com/ls2/faq/index.jsp
http://www.ucar.edu/communications/infopack/lightning/faq.html

Mephisto
06-01-2002, 03:12 PM
I don't know if the lightning actually struck my house or if I experienced a "near miss," but one of my stereos sure got fried during a pretty scary electrical storm last year. No other damage, though, thank God.