You must have noticed the signs. Longer, hotter summers. Shorter, milder winters. Birds arriving on their breeding grounds weeks before they once did.
So, why not just enjoy the weather? Because what seems like a change for the better is really a cause for grave concern. Today, the Earth is heating up faster than at any other time in 10,000 years. The reason is the greenhouse effect. Just as a greenhouse captures the sun’s warmth, greenhouse gases trap heat in the Earth’s atmosphere. When we burn coal, oil, and natural gas to fuel factories, communities, and automobiles, we add greenhouse gases to the atmosphere. Since the start of the Industrial Revolution in the early 1700s, greenhouse gas concentrations have risen sharply: carbon dioxide (CO2) by 30 per cent, nitrous oxide by 15 per cent, and methane by 100 per cent. These increases heighten the greenhouse effect, raising global temperatures and causing the planet’s climate to change.
That is why extreme weather events, such as tornadoes, hurricanes, and radical swings between deluge and drought, are becoming more common. Polar ice caps are shrinking. Mountain glaciers are melting. Sea levels are rising. Lake levels are falling. Meanwhile, biological impacts of climate change are becoming more evident. Many species are relocating, migrating sooner, and bearing young earlier than in the past. Fish from southern waters, like great white sharks and Pacific blue marlin, are appearing more frequently off Canada’s coasts. Coral reefs worldwide are dying off. Amphibians are declining globally. Entire ecosystems are shifting and wildlife habitats vanishing. The most dramatic changes of all are taking place in Canada’s Arctic, which is heating up faster than anywhere else. Here, northerners are watching in disbelief as the permafrost melts beneath their feet, Pacific salmon are caught for the first time, and sea ice shrinks away from the coast.
While the science of climate change is still evolving, most experts predict a dramatic shift in environmental conditions worldwide. Scientists anticipate that CO2 concentrations will triple by the end of this century. By 2100, average global temperatures could rise by 1.5 to 4.5°C. In some parts of Canada, temperatures may increase by 5 to 10°C. This rapid warming of our oceans and atmosphere could result in climatic changes greater than humans have ever seen.
To determine which regions are at risk and how, experts use computer-generated global circulation models. These models show that aquatic ecosystems are especially vulnerable because of their limited ability to adapt to climatic changes and that, as a northern nation with a longer coastline and more freshwater than any other country, Canada may be among the hardest hit. What else do they forecast?
- As temperatures rise, ocean waters may expand and polar ice caps, glaciers, and sea ice could melt faster than before, raising sea levels by up to one metre, causing higher tides, submerging islands, eroding shorelines, flooding coastal wetlands, and polluting ground and surface waters.
- Extreme weather events, such as hurricanes, typhoons, and tornadoes, may happen more often, with more severe impacts on coastal and inland areas.
- Rain and snow could increase in some regions like the Great Lakes but decrease in others like the Prairies.
- Increasing cycles of drought and flood may stress freshwater resources, lower river and lake levels, and make it harder to cultivate crops.
- Higher water temperatures could change the course and intensity of major ocean currents, disrupting entire ecosystems, and altering the dispersion of nutrients and warmth that sustain marine life.
Wildlife in Hot Water
Climate change could mean troubled times ahead for an untold diversity of aquatic life, from the equator to the ends of the Earth:
- The fate of countless plants and animals may depend on their ability to move from unfavourable climatic conditions to ones that meet their survival needs. Those that are endangered, slow moving, or isolated in fragmented areas could find themselves stranded.
- Migrators whose arrival and departure dates are no longer in sync with the rhythms of nature could miss the food sources they need to survive, the warm weather they need to breed, and the wind and ocean currents they need to travel.
- Changing distributions, migration patterns, and growth rates of salmon, cod, and herring may disrupt commercial fisheries.
- Heavier rainfall in coastal regions could result in more polluted run-off entering estuaries and bays, which provide food and shelter for fish and shellfish and are important stopovers for migratory birds.
“The time has come,” the walrus said, “to talk of many things…”
One of the things the walrus talks about in Lewis Carroll’s poem is “why the sea is boiling hot.” Nowadays, warmer seas may well be a topic of conversation among walruses lounging on ice floes in Canada’s Arctic. The many grunts, growls, barks, and bellows emitted by these massive marine mammals could be their way of lamenting the loss of the habitat that gives them life.
Among the fastest-warming regions on Earth, the Arctic may face the worst impacts of climate change in the 21st century. Scientists predict the continued melting of sea ice: a vast, frozen platform that has already thinned by 40 per cent in recent years yet is indispensable to the survival of walruses, polar bears, king eiders, narwhals, and countless other creatures.
Ranging from Canada’s Eastern Arctic, down to James Bay and the Labrador coast, across the North Atlantic to the Kara Sea, the walrus is no longer found in the Northwest Atlantic, Mackenzie Delta, or St. Lawrence River. Its disappearance from these regions was the result not of climate change but of commercial hunting in the past. Remaining walrus populations have largely recovered in the Eastern Arctic and are now hunted only by indigenous people, who use every part of the animal’s body for food, carvings, hides for covering kayaks, and other practical purposes.
The walrus itself makes the most of nature’s gifts to eke out an existence. This one-tonne, two-tusked heap of wrinkles, blubber, and whiskers is perfectly adapted to survive in the Arctic seas, whether using its thick skin and folds of fat to withstand the frigid temperatures, diving to depths of up to 100 metres with the help of its powerful fins, or using its tusks to fend off polar bears or to dig for clams on the ocean floor. The question is whether the walrus can adapt to the challenges of climate change.
What Is Being Done?
Climate change is a global problem. All the world’s nations must work together to find solutions, especially heavily industrialized countries whose populations and greenhouse gas emissions are increasing rapidly. To meet this challenge, Canada supports international efforts aimed at minimizing quantities of greenhouse gases entering the atmosphere.
Across this country, governments, industries, schools, communities, and individuals are taking action to curb climate change and address its impacts. Their efforts include improving the management of aquatic and terrestrial habitats; supporting climate change and atmospheric research; increasing energy efficiency in buildings and automobiles; and developing renewable energy sources, such as wind turbines and solar power, as well as fuel cell technology.
Can You Help Turn Down the Heat?
Get informed about climate change and its impacts on aquatic wildlife and habitat. Then, undertake ocean action projects, conserving food, water, shelter, and space for species threatened by climate change. Choose projects that protect the natural ability of terrestrial and aquatic ecosystems to absorb greenhouse gases and maintain a healthy climate; that help isolated species meet their needs by improving connectivity between fragmented habitats; and that buffer the impacts of climate change on marine habitats.
Do everything you can to reduce greenhouse gas emissions by encouraging energy efficiency and promoting non-polluting energy sources at home, at school, and in your community. Contact public officials and urge them to develop and strengthen programs to encourage energy efficiency and renewable energy; raise fuel economy standards for cars and trucks; set strict limits on greenhouse gas emissions from power plants; improve efficiency standards for electronics and home appliances; and ensure the sound management of marine ecosystems.
Celebrate Oceans Day!
You and your community can commemorate Oceans Day in many ways:
- Create an Oceans Day display addressing climate change or another theme at your local library, school, or community centre.
- Encourage family, friends, and neighbours to dispose of household hazardous wastes, such as batteries, motor oil, leftover paint, and solvent containers, at proper waste disposal sites rather than dumping them down the drain.
- Link up with another community — coastal or inland — in a distant part of Canada or the world and collaborate on ocean awareness activities or action projects.
- Recruit volunteers to clean up a beach, river, wetland, or coastal area through local media, posters displayed in community centres and schools, and by contacting youth groups.
- Write letters to the editor of your local newspaper expressing your concerns about ocean health.
- Circulate a petition voicing your concerns about climate change or another environmental problem and suggesting solutions; send the petition to the prime minister, a Member of Parliament, or other environmental decision-maker.
- Prepare a news release or public service announcement describing your Oceans Day activities; submit it to a local newspaper or radio station.
- Persuade your town council to officially declare Oceans Day, June 8, and implement ocean-action projects.
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