Flashcards in Boscastle Deck (19):
when did the flooding occur?
16th August 2004
where is it located?
on the coast of cornwall at mouth of the river valency, in the south west of Britain
on which day did the meterological agency forecast heavy rainfall?
16th however couldn't say where it would develop
how long for and how much rain dropped?
200mm in around 24 hours
how did the storm occur?
from a large depression of low pressure over the atlantic . warm air from the sea met with warm sunshine producing huge clouds
what type of rainfall occurred?
how does convectional rainfall occur?
warm moist air rising and cooling causing water vapour to condense and rain to fall
how much water flowed through Boscastle?
2 million tonnes
what was the peak discharge?
how long was the lag time?
what type of rock is in the area?
Millstone grit - sandstone however was impermeable due to antecedent conditions
size and shape of the drainage basin for the river valency?
small and round around 30km^2
topography - steep
antecedent conditions 50mm in 2 hours early afternoon
cars - one trapped under bridge water build up
little flood defences
land use - urbanisation
how were local ecosystems affected?
debris from buildings may have damaged the ecosystems
how many buildings were destroyed?
6 causing temp loss of economy
how many homes were destroyed?
how much debris was removed in the clean up operation?