Transcript Changing Seasons in a Changing Climate Part One

Changing Seasons in a Changing Climate
Part One
A very personal
concern
book research and years of
observing nature have made me very
aware of seasonal change and “what
is normal”
• a growing awareness that the usual
dates of events in nature are
changing, as well as the numbers and
kinds of many plant and animal
species
• a growing sense of loss
• frustration that climate change
story is not really being told and in
the lack of any meaningful action
•
Algonquin Park 1963 with Doug Sadler and Haig
Kelly
Bird in hand – Wallis Drive – 1963
Climate Change in a nutshell
•
•
•
•
•
Known by numerous names: global warming, climate change, climate weirding
and, increasingly, climate disruption
By adding extra carbon dioxide to the atmosphere through human activity, extra
heat is trapped, and the atmosphere gets warmer than it used to be
A warmer atmosphere can hold more water; warmer oceans = more evaporation
which means greater precipitation
We are seeing more extreme storms, more severe droughts, deadly heat waves,
rising sea levels, and more acidic oceans, which can affect the very base of the
food chain. Mass extinctions (20 to 50% of all species) are forecasted for this
century.
“Connect the dots between fossil fuels and severe weather events, such as the
recent Alberta floods, Quebec’s wildfires and flash floods in Toronto, where rainfall
shattered all one-day records. This is what climate change looks like in Canada.”
Letter to the Editor The Globe and Mail, July 10, 2013
•
Insurance claims for water, hail and wind damage have soared in the past 10 years.
By the numbers
•
•
•
•
•
•
•
•
•
•
CO2 levels in the atmosphere reached 400 ppm in May. Highest in least 3.2 million
years. However, 350 ppm is considered the highest “safe” level.
In Peterborough 39 of the past 45 months have been warmer than the 1971 –
2000 average
For Canada as a whole, 2010 was the warmest year on record since records began
2010 was the wettest year on record worldwide
2001 to 2010 was warmest decade ever world-wide with record flooding
2012 was Southern Ontario’s warmest winter ever
Ice coverage on the Great Lakes has decreased by 70% since the 1970s.
In past 65 years, Canadian winters have warmed by 3.2 C (twice global rate)
97% of 1,372 of the world’s most active climate researchers (whose work has been
reviewed by National Academy of Science in the U.S.) blame human activity for
climate change
The 2013 Intergovernmental Panel on Climate Change (IPCC) report states that “It
is extremely likely [95 percent confidence] that human influence has been the
dominant cause of the observed warming since the mid-20th century.”
WINTER
Climate change is being felt most
acutely in late fall, winter & early
spring
Average winter temperatures
predicted to rise from 3 - 7 C this
century, depending on how much
is done to reduce greenhouse gas
emissions Already 6 C warmer
than average in winters of 2012
& 2013
Impact on hibernating frogs
Wood Frogs, Spring Peepers and Chorus Frogs overwinter in the leaf litter and
essentially freeze solid. Increased freeze and thaw episodes disrupt hibernation and
consume valuable energy.
Wood Frog
Chorus Frog
Changes in bird populations in the Kawarthas
Thanks to milder winters and bird feeders, “southern birds” have increased in number
and have expanded their range northwards compared to 30 years ago.
Red-bellied Woodpecker
Mourning Dove
Northern Cardinal
Northern Mockingbird
Tufted Titmouse
Future is good for
White-tailed Deer
but bad for Moose
• Winter survival for deer will be easier as
food will be more accessible and there will
be less snow cover
• Moose, however, may be forced further
northward as deer populations increase
(brainworm parasite)
• Moose are declining drastically in many
parts of their range, esp. southern regions
• 70% decrease in Minnesota since 2006,
where all hunting is banned
• Ronald Moen of University of Minnesota
believes decline correlates with the warmer
summers & winters (e.g., long, hot summers
stressing the animals & compromising
immune systems); milder winters making for
more mortality from winter tick, etc.)
Less winter mortality
for insects
Milder temperatures are allowing more
insects to successfully overwinter.
•Possibly explains the increase in West Nile
disease in 2012. Worst year ever in U.S.
House Mosquito (Culex
pipiens)
• Lyme disease is present along Lake Erie
and Lake Ontario as Black-legged Ticks are
now able to overwinter in Ontario. Will
have spread over all of Southern Ontario
by 2020. May already be in the Kawarthas.
• Insects in general – including pests should thrive in a warming climate and
have more lifecycles.
Black-legged Tick
Late winter is mating time for many mammals *
Generalists mammals like skunks and raccoons are
also expected to prosper in a warmer climate.
Virginia Opossums, a
southern species, are
already extending their
range into the Kawarthas
as winters become warmer.
SPRING
• Earlier and warmer springs are being
predicted
March 2012 saw:
• Frogs calling four weeks early
• Mourning Doves beginning to nest
• Flower buds on apple trees opening a
month early. Many flowers were killed
by April frosts, resulting in an 80% loss
in Ontario’s apple production.
• Ice-out on March 20, a full month
earlier than the long-term average
Some short-distance migrants are, on average, returning
earlier as spring becomes earlier
Common Merganser
Red-winged Blackbird
Great Blue Heron
American Robin
Hooded Merganser
Mating season
continues
* Early spring is mating season
for mammals
with a short gestation period
* With warmer winters,
Southern Flying Squirrels are
moving north and some are
mating with Northern Flying
Squirrels, a different species
* Akin to Polar Bears and
Grizzly Bears mating
•Hybrid squirrels are becoming
increasingly common
• Being explained as an effect of
climate change
(Trent University/MNR study)
Nesting season
begins
- earlier springs are resulting in
an earlier start to the nesting
season for resident birds &
short-distance migrants
- these species should be able
to breed earlier and raise more
young
- One large-scale study showed
that birds are laying eggs up at
an average rate of 6.6 days
earlier per decade
Mourning Dove
An earlier spring frog chorus
•
Peak calling period of early breeders is now 10
– 20 days earlier than in 1995. Spring Peepers,
Wood Frogs, Chorus Frogs and Northern
Leopard Frogs (MNR study published in
Herpetological Conservation and Biology, 2012)
•
Eggs are laid in vernal ponds which are
temporary bodies of water. Drier summers may
mean that these ponds may dry up before the
young frogs and salamanders have had the time
to develop to the adult stage
Spring Peeper
Chorus Frog
Salamanders are mating earlier, too.
Migratory
butterflies arrive
-Unprecedented numbers (300 million
plus) of Red Admirals arrived in spring
of 2012
- was due to conditions in Texas
where abundant rain followed a
devastating drought (climate change?)
- all predatory insects were killed off
by the drought
- with the rains, wildflowers were
abundant and huge reproduction
success
- wave after wave came north out of
Texas from April through May
- arrived too early to reproduce here
since nettles, their host plant, had not
yet emerged
- Monarchs arrived early, too, in some
areas before milkweed were up. Poor
reproductive success.
Red Admirals feeding on tree sap
Climate Change and
Butterfly Emergence
Study by UBC, University of Sherbrooke
& University of Ottawa in Global
Change Biology (November 2013) has
found that butterflies are highly
sensitive to temperature
Emerge on average 2.4 days earlier per
degree Celsius of temp. increase.
Warmer temperatures will mean
butterflies will emerge earlier
By merging too early, they could
encounter frost and die. Or they might
emerge before the food plants they rely
on appear and starve
Even a slight decline in butterfly
population will have consequences for
other species going up the food chain.
Spring Azure
Earlier flowering of trees
Red Maple
Speckled
Alder
Carolina
Poplar
Silver Maple
An earlier black
fly emergence
- Black flies are now in peak
numbers in late April through
early May
- in the 1960s, peak numbers
were not until mid- to late May
- traditionally, May 24th
Weekend saw the worst black
fly conditions
A dusting of
pollen descends
from the skies
With climate change, tree pollen
is emerging roughly two weeks
earlier in the spring in much of
North America.
Pollen counts are expected to
more than double by 2040.
Many people are experiencing
more serious allergy symptoms .
•
Spring ephemeral wildflowers bloom
In recent years, peak bloom has been two to three weeks earlier than normal
Red
Trillium
Jack in the
Pulpit
White Trillium
Wild
Columbine
May: Long distance migrants arrive
Their arrival may no longer coincide with peak insect numbers, leading to less reproductive success. Some species
may extend their range northward and therefore no longer nest in the Kawarthas.
Costa Rica
Yucatan, Mexico
Argentina
Brazil
Panama