lecture 3 Flashcards
Russian fires of 2010 due to:
Anomalous high pressure temperatures - large area burned and caused bad air quality and associated health problems
Russian fires and asian floods linked meteorologically is an example of what?
Variability inherent in the atmospheric circulation - unusual and a distinct anomaly
What criteria for storms is considered climate change?
More frequent storms/bigger storms over 30 year period
Associated flood impacts
What determines major weather patterns and weather experienced in a place
Atmospheric circulation and latitude
Atmospheric circulation is driven by:
energy exchanges at the equator-pole heat differential
Climate change is:
If changes occur in atmospheric energy over a
period of time (usually at least decades), the
general circulation patterns are likely to shift,
changing, on average, the weather experienced in a
particular place (more storms, more droughts,
changed monthly averages, etc).
Climate
An emergent property of weather
Average weather of a place or region
Statistical descriptions of long-term weather
Climate is composed of a set of variables:
temperature, pressure, precipitation, wind, humidity
etc.
Their key properties are spatial patterns, temporal
trends, mean (and variance) and variability.
Variation
describes the spread in a set of values that are
observed. This can be described, for example, as the total
range from highest to lowest value
Variance
as a statistical term it has a precise meaning. It
measures how far a set of numbers is spread out around the
mean. A small variance means the measurements are tightly
clustered about the mean, a large variance that there is much
variation around the mean. In climate terms, a set of
measurements that have low variance would mean that a
variable was rather consistent and changed little (think tropical
vs temperate zone temperatures).
Variability
as used with climate, describes how much variation
occurs – say in temperature – across space or through time. A
highly variable climate record suggests large swings in values
(much variation), and thus perhaps a degree of unpredictability
(from day to day or year to year). Variability is an important
property of climate (as any farmer would tell you).
Anomaly maps
compare two states via difference, here temperature simulated for future decades minus present values
intra-annual climate data shows
seasonal patterns,
short-term variability—a seasonal or monthly value
can be compared with a longer-term mean
Inter-annual climate data shows
variation from year to year
Inter-annual records are averaged as what?
30-year means or normal periods - most recent 3 decades used for the purposes of comparison
