This document discusses drought and climate change. It notes that drought is a natural part of the climate in some regions, but that climate change is exacerbating drought conditions. As the global water cycle intensifies with climate change, dry areas are expected to become drier and wet areas wetter. The data and climate models support this trend. The document also explains that drought is defined by insufficient water to meet demands, with both natural and human factors influencing supply and demand. High temperatures from climate change act as an additional stress. The author argues that communities must prepare comprehensive plans to manage drought risks.

1. Drought
and
Climate
Deke
Arndt
11
March
2013
Monday, March 11, 13 1

2. Two
Guarantees
on
Drought
• This
drought
will
end
• There
will
be
another
drought
Monday, March 11, 13 2

3. Drought
and
Climate
• Some
parts
of
the
world
(par@cularly
interior
of
con@nents)
are
naturally
prone
to
big
swings.
• Dryness
is
part
of
the
climate;
so
is
drought
• Lots
of
complex
defini@ons,
with
a
helpful
simplifica@on:
• not
enough
water
to
meet
needs
• Drought,
unlike
other
hazards,
is
about
supply
and
demand.
• There
is
a
supply
component:
rain,
snow,
precipita@on
• There
is
a
demand
component:
human,
natural
• There
are
ar@ficial
constructs
of
each:
reservoirs,
water
extrac@on
Monday, March 11, 13 3

4. Drought
and
Changing
Climate
• Increased
vigor
in
water
cycle
• Rules
of
thumb
(sweeping
generali@es
with
many
local
excep@ons):
• Wet
places
geOng
wePer;
dry
geOng
drier
• Wet
seasons
geOng
wePer;
dry
geOng
drier
• Big
Rain
episodes
geOng
bigger
• These
are
predicted
by
climate
science
• These
are
borne
out
by
the
data
• 2011
emblema@c
of
this
Monday, March 11, 13 4

5. Drought
and
Changing
Climate
• Going
back
to
concept
of
supply
and
demand
• Big
Heat:
An
addi@onal
“Tax”
in
the
supply
and
demand
equa@on
• 2012
emblema@c
of
this
“Green
Up”
and
“Brown
Down”
of
the
• Area
of
“severe”
drought
U.S.
Midwest
during
the
drought
expansion
of
2012.
(from
Karl
et
al.,
2012
increased
by
11%
due
to
high
–
Nov
20
issue
of
Eos
temps
in
spring
2012
Monday, March 11, 13 5

6. Lake
Michigan-­‐Huron
Monday, March 11, 13 6

7. Drought
Is
Rarely
Like
This
Monday, March 11, 13 7

8. Drought
Isn’t
Sexy
• Drought
impacts
not
always
so
visible
• Drought
is
about
supply
and
demand
• No
screaming,
no
chasing,
no
“debris
ball”
signature
on
radar
• Prepare
for
violent
weather
by
building
structure
• Prepare
for
drought
by
building
a
plan
• Violent
weather
tests
structures
• Drought
tests
communi@es
• Violent
weather
leaves
visible,
drama@c
debris
• What
is
the
debris
of
drought
• Violent
weather
a^er-­‐school-­‐special
ending:
“we’ll
rebuild”
• What
is
the
a^er-­‐school-­‐special
ending
for
drought?
Monday, March 11, 13 8

9. Thank
You
Monday, March 11, 13 9