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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”
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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 ppmis 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 partly to milder winters, “southern birds” have increased in number and have expanded their range northwards in Ontario compared to 20 years ago. Red-bellied Woodpecker House Finch Wild Turkey Northern Mockingbird Tufted Titmouse
Future is good for White-tailed Deer but bad for Moose Winter survival 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 already declining drastically in many parts of their range across the Northern Hemisphere and especially in more southern regions 70% decrease in Minnesota since 2006, where all hunting is banned Ronald Moen of University of Minnesota believes the decline correlates with the warmer temperatures being produced by climate change but more research needs to be done
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. • 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. House Mosquito (Culex pipiens) 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 American Robin Great Blue Heron 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 Spring Peeper • 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 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 Carolina Poplar Red Maple Silver Maple Speckled Alder
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 White Trillium Red Trillium Jack in the Pulpit 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 Panama Argentina Brazil