forecasting

Question 1

how much is forecasting worth?

Answer 1

extremely valuable estimated at $31.5 billion per year, public values met office at £353.2. million

Question 2

what is prediction?

Answer 2

is a weather forecast, initial conditions are known

Question 3

what is a projection?

Answer 3

no intial conditions are known, climate models are driven by projected future greenhouse gases

Question 4

when was first forecast?

Answer 4

mid 1950s first numerical weather forecast, first operation forecasts were in late 60s

Question 5

when did forecasting begin?

Answer 5

all started around the same time mainly due to the shipping industry

Question 6

what is a deterministic forecast?

Answer 6

single model, good for out to 48 hours, longer than this errors begin to propagate too much, not coupled to ocean models

Question 7

what is a probabilistic forecast?

Answer 7

Lorenz 1960s realised small errors in initial conditions propagate in the fore cast, its an ensemble of lots of runs (50+) of the model with slightly different initial conditions to get a good estimate

Question 8

what is a medium range forecast?

Answer 8

it is an atmospheric low resolution model, 15 day forecast, ensemble of low resolution forecasts providing a reliable estimate

Question 9

what is an extended medium range forecast?

Answer 9

low resolution 32 day forecast. twice a week extended up to 32 days

Question 10

what is a seasonal forecast?

Answer 10

lower resolution extending 7 months, coupled to an ocean model

Question 11

what is nowcasting?

Answer 11

combination of observation with forecast products 0-6 hours ahead