So far away, and yet so close.

It's 2050.

Read any report on climate change and, chances are, that date will stare back at you.

It's frequently set as the year when we can expect a long, frightening list of devastating impacts, including decimation of the oceans' fish and the planet's forests; an ice-free Arctic; hordes of starving environmental refugees seeking new homes; and the extinction of a million animal species.

But Canada's main political parties and the governments of many countries also cite 2050 as the target by which to achieve massive cuts in greenhouse gas emissions.

Why that year?

Part of its appeal is that it's a middling distance into the future.

It's soon enough that the majority of people alive today can still expect to be breathing then. That makes it real. Despite professions of concern for future generations, it's difficult to stir passions or action about something that will happen a century or two or three from now.

As well, most of the things we build, including generating stations, roads and major industries, last 40 or 50 years. So what we do now will play a large part in determining what the Earth is like in 2050.

"It's a useful year to focus on," Matthew Bramley, director of climate change at the Pembina Institute, which does environmental policy research, said in an interview from Ottawa. "It's far enough away to be a year when real change is both necessary and possible."

Anyway, longer-term forecasts are likely irrelevant.

If we make the wrong decisions now, scientists warn, by 2050 the planet will either be a mess or irretrievably on course to become one. Viewed from the opposite direction, it's when major changes must be completed if we're to avoid disaster.

So, what will the Earth be like 43 years from now?

While most general predictions are consistent, details remain a bit of a guess. Much depends on whether we make a concerted effort to reduce greenhouse gas emissions and other pollution between now and then, and on what steps we take to adjust to the new environment.

It's certain the world will be warmer. With all of the carbon dioxide already in the atmosphere, the planet is, on average, 0.6C warmer than at the start of the Industrial Revolution - when we began burning fossil fuels in vast quantities - and there's no way to keep it from climbing another half a degree. The stuff stays intact for about a century, and we're stuck with it.

Even with very stringent emissions cuts, scientists say the average temperature by the end of the century will be at least 2C above pre-industrial levels. In fact, they say, that's the best we can hope for.

It's a small number but a substantial increase, and it will cause hardship for many people. Still, with effort, we could adapt to the changes in temperature, precipitation and water supply that would likely result.

To stay within that limit would require major changes in technology. Current crystal balls show lines of giant wind turbines and machines that generate electricity from wave power a few kilometres off ocean coasts; massive centralized power stations fuelled by coal that capture all their greenhouse gas emissions and pump them deep into the ground; well-insulated homes heated or cooled by underground geothermal energy; solar panels everywhere; zero-emission cars.

Of course, technology changes rapidly and often in surprising ways, so we might go off in totally unexpected directions to meet our inevitably soaring energy demand and be much better off than anyone now hopes.

But we're also resisting change, which makes it more difficult to curb the warming trend. Bare land and open water absorb much more heat than earth covered in trees or snow, or frozen seas. Melting permafrost could release immense amounts of methane, a very potent greenhouse gas.

So most predictions for 2050 assume we'll zip past the two-degree target. As now, we'll gradually use energy more efficiently. But those gains will be far outstripped by population and economic growth.

These attempts at future gazing, too, contain considerable guesswork. Experts plug numbers into sophisticated and massive computer programs that often take months to spit out results. Others look at history and trends, and make assumptions.

Forecasts for the entire planet are considered the most accurate. Precision decreases along with the size of the area being studied.

With all of this in mind, what follows is a picture of the world in 2050, a picture compiled from a wide variety of reports and interviews.

Up to one-third of the global population - about 9 billion in 2050 - lacks water. The shortages are worst in the areas of Asia and South America that get their supply from melting glaciers in the Himalayas and Andes mountain systems. Those rivers of ice have melted away.

Some parts of Earth, including much of Canada and Europe, get more rain, but others - notably southern Africa, Australia and the Mediterranean Basin - are parched by drought.

Mediterranean tourism has withered away; the beaches are blistering hot. But people flock to toasty warm northern Europe and Britain, where they can sit under palm trees and munch on locally grown olives.

And if it's business as usual?

It's warmer in most places, particularly in winter. In the first couple of decades after 2007, a few areas here and there cooled down from time to time, as natural cycles asserted themselves over human-caused climate change. By 2050, though, that kind of impact is history: Climate change rules.

The biggest temperature increases are in the Arctic and over Africa and the Middle East.

The poles get more precipitation, the mid-latitudes less. Drought threatens southern Africa, the Middle East, Southeast Asia, northern South America, and the central and southeast United States.

We've just seen the first summer with no ice at the North Pole. Canada's High Arctic is, on average, a huge 5C or 6C hotter than in the past. Ships can now ply the Arctic with relative ease.

Inuit have many more weeks in which to zip across the waves in boats, but they no longer see polar bears or walruses, and seals are rare. With Arctic winter temperatures 5C to 8C higher than in recent history, ice conditions are treacherous and travel dangerous.

Most of British Columbia and the Prairies have the least warming, winter and summer, but even they are two or three degrees above the late-20th-century average. They'll also get less precipitation.

In Toronto, winters are mild and drier. Outdoor ice rinks are distant memories. Summers are hot and sticky - three or four degrees above the turn-of-the-century average. Smog blankets the city almost every day, although the cruddy haze is often shredded by violent thunderstorms, which overwhelm the sewer system, causing floods and erosion and flushing vast amounts of human and toxic wastes into Lake Ontario.

The Humber, Don and Rouge rivers are increasingly erratic, and with the intense bursts of rainfall, it's no longer news when they overflow their banks.

With increased evaporation and slightly reduced precipitation, the levels of Lake Ontario and the other Great Lakes have dropped a metre or two. Storm-whipped water and occasional flash floods make living near the shore a dicey proposition.

Farmers are frustrated. Their crops should be thriving on the feast of carbon dioxide in the air and the longer growing season. But the heat is often too scorching: Even worse, precipitation comes in violent, damaging storms that punctuate prolonged droughts.

In the tropics, the growing season has actually been shortened by heat, and crops are parched.

Around the world, about 1 million land-based plant and animal species have gone extinct. More than 90 per cent of the oceans' coral reefs, including Australia's Great Barrier, have died off. The sea species we eat have virtually disappeared from the oceans, and farmed fish can't fill the void.

The "bread basket" of the United States - the Great Plains of the Midwest - is now too hot for wheat and other cereal crops. The prime growing area has shifted. It begins in the northern U.S., covers almost all of Canada's prairie provinces and stretches up to the southern Northwest Territories. Unfortunately, much of the land is the Canadian Shield, with thin soil that can't support grains. But there are pockets of good growing land.

Much of the vast boreal forest that once covered the rocky shield has disappeared; it simply couldn't survive the hot, dry climate. Forest fires are larger and more frequent. The decline of the boreal has been the death knell for the woodland caribou, wolverine, Canada Jay and many other species.

Other forests have been decimated by disease and insects that are no longer killed off by cold winters. Pests have a longer growing season in which to attack trees and produce offspring. That produces yet another feedback, since dying and dead trees stop storing carbon.

On average, everyone on Earth is 20 per cent poorer. But the economic burden isn't spread equally. Places like sub-Saharan Africa that are already impoverished fare even worse.

Rising sea levels and the spread of deserts have forced as many as 200 million people to seek new homes as environmental refugees. They're flooding into Europe, North America and Australia.

Malaria is spreading because mosquitoes that carry it can survive in more areas, but the disease hasn't yet reached Canada.

International tourism will have shrivelled because of restrictions on air travel - which by now is one of the major sources of greenhouse gases.

Warm winters long ago wiped out Europe's ski industry. Now, Rocky Mountain resorts in Canada and the U.S. are going under.

The Netherlands, after centuries of wresting land from the sea, has had to give much of it back. Thousands of people are living in floating communities.