An Excursion across the Continents - Remote Sensing Application - Completely Remote Sensing, GPS, and GPS Tutorial
An Excursion across the Continents

The many Landsat images spread over the next 6 pages that comprise Part 2 of this Section have mostly been selected from the master set used in developing the 1976 NASA publication Mission to Planet Earth: Landsat Views the World, using imagery acquired by Landsat 1. Scenes made by other earth-observing satellites and as photos on the ground are also used in this excursion The description associated with each Landsat image is extracted from the captions in that book; consult it, NASA SP-360 (residing in many libraries), for more extensive descriptions of the scenes reproduced in the following Tutorial pages. Recall, too, that you have already seen a number of foreign images, e.g., specifically, London, Paris, Florence, Peking, Tokyo and other cities on page 4-4 and the Game preceding this page in this Section.

Canada

Our trip to view examples of the Rest of the World begins in Canada. Canada is the third largest - areawise - country on Earth, although its population is around 40,000,000. Here is a mosaic of Canada, made by Earthsat from Landsat images, and below it a map of this country with its principal cities (note: Canada has Provinces, not States):

The physical landscape of Canada, made from individual Landsat images.
Map of Canada showing major cities.

We'll begin with Newfoundland. A popular attraction on its north coast is L'Anse aux Meadows, now considered to be the first place in North America visited by Europeans. The Vikings landed there and stayed for a while, building sod-covered dwellings to protect from the harsh winter. Carbon-dating of fire embers places this around 1000 A.D., thus preceding Columbus by almost 500 years. Here is an ASTER view of the area, at the northern tip of Newfoundland, and a ground photo:

ASTER view from space of the L'Anse aux Meadows historical site.
Ground view of earthen shelter; the fence is modern.

Off the east coast of Newfoundland is a curiosity that almost no American knows anything about. There are three islands that are still the property of France - a vestige of the days when Canada was a French possession. They collectively are known as St. Pierre and Miguelon. Comprising just 93 square miles, they host only about 7000 inhabitants. In the ASTER image below note that the two larger islands are connected by a natural sand spit called a tombolo.

St. Pierre and Miguelon.

Labrador is one of the premium regions in Canada to see the styles of deformation in ancient (Precambrian) terrains. These next three images show 1) another space image in which the black and white rendition brings out fractures and other structures, 2) an oblique aerial view of the bleak scenery, and 3) a detailed aerial photo showing style of folding.

Labrador: crystalline rock terrain with megafaults
Aerial view of the Labrador Shield rock landforms.
A strongly folded metasedimentary assemblage.

In eastern Canada, Nova Scotia is a Province in the Maritimes. This image shows the Cape Breton Island (this becomes an "island" because the narrow Strait of Canto cuts across its southern boundary), and other parts of northern Nova Scotia and the tip of Prince Edward Island.

Cape Breton and surroundings; this 'island' contains low mountains.

Cape Breton boasts of the most rugged coastal scenery in the accessible eastern part of the North American continent. Its Cabot Trail is famed for its scenery.

Part of the west coast of Cape Breton, along the Cabot Trail.

Between Nova Scotia and New Brunswick is the great indentation known as the Bay of Fundy. The Bay is noted for its extremes in water level fluctuations. The Bay of Fundy has the largest variations in tide levels in the world - as great as 17 m (56 ft), resulting from the tidal bore effect caused by the tapering and shallowing of the Bay floor. Timing of the tides could contribute by helping the in and out surging waters to "resonate". This pair of Terra ASTER images shows the tidal extremes around Cobequit Bay in the Minas Basin:

High (top) and low water levels in this part of the Bay of Fundy; note the extent to which the land is exposed at low tide.

Moving northward into an area where eastern Quebec meets the western boundary of the Labrador subprovince of Newfoundland, we see next a segment of the Canadian Shield. This is the Labrador Fold Belt, made up of tightly folded sedimentary rocks wedged between two granite complexes. The structures represent an ancient (Precambrian) tectonic zone formed when one irregular continental mass collided with a sedimentary basin; the entire region has been much eroded to form "roots of mountains". The present surface is strongly glaciated, leaving low hills and lakes and a paucity of trees so that rock exposures are widespread. The high northern latitudes favor an arctic-like vegetation assemblage called tundra. This inhospitable landscape is very sparsely populated, with a few small towns built near iron mines.

) The Labrador Fold Belt in northeast Canada, a tundra landscape with muskeg.

Less well traveled by tourists, but still replete with interesting places, is the Gaspe Peninsula, south of the St. Lawrence River:

The Gaspe Peninsula.

The next scene covers some of the Eastern Townships in heavily forested (spruce; fir; pine; tamarack; birch; maple) hills in the Laurentian Lowlands of the Province of Quebec. The St. Lawrence River appears in the upper left and glacially-elongated lakes are scattered throughout the scene. The most striking feature throughout the image is a distinctive pattern of land-clearing by deforestation that stands out as elongate bars with jagged edges. Their lighter red color shows them to be grasslands. These long strips tend to be perpendicular to roads and small streams. They are a land use pattern brought over from France and adopted by the early French settlers (seigneurs) who colonized this region in the 1600s; the Cajuns around New Orleans used this style.

Heavily forested (and clearcut) hills of southern Quebec, not far from the northwest part of Maine.

The capital of the Province of Quebec is Quebec City, one of the oldest settlements in North America, founded by the Frenchman Samuel de Champlain in 1609. It was here that the battle of the Plains of Abraham in the Seven Years War in 1759 that the British General Wolfe defeated the French General Montcalm (although both were killed during the conflict), which led to France ceding Canada to England in 1763. We see the city in a SPOT image and in a ground photo which shows the bluffs along the St. Lawrence River and the Chateau de Frontenac, a plush hotel that is part of the Canadian Pacific rail system.

SPOT image of Quebec City.
Quebec City, with the Chateau de Frontenac.

Most of Canada's cities lie in regions near the U.S-Canadian border. Here is a Landsat image that shows Montreal, Canada's second largest city, and its surroundings. Note the elongated farms which follow the "long lot" style characteristic of France (and seen again around New Orleans, once settled by French Canadians).

Landsat subscene including Montreal, Quebec on the St. Lawrence River.

This SPOT-4 panchromatic image shows much of the central part of Montreal.

SPOT image of Montreal, Quebec, on the St. Lawrence River.

And here is this city as seen from the ground, in the early evening:

Montreal, Quebec, Canada.

Here is a Landsat 7 image of the western half of Canada's capital city, Ottawa:

Part of Ottawa, Canada; the farmland in the midst of the city is the government experimental agricultural complex.

The red rectangles are part of the government's experimental farms located within the city.

The largest city in Canada is Toronto, at the northwest end of Lake Ontario. Here are two views of the city from space:

Space image of metropolitan Toronto extending around Lake Ontario through Hamilton and southern towns.
Landsat image of metropolitan Toronto.

The Quickbird satellite has produced this high resolution of downtown Toronto's tall buildings:

Quickbird satellite 2 meter image of Toronto.

Compare this scene with the ground photo showing Toronto's skyline. The tall needlelike structure on the left is the CN Tower, the city's best known landmark.

The Toronto skyline.

Most of the Canadian Shield in the eastern two-thirds of Canada is undeveloped, with few towns. Forests - both coniferous and deciduous - are still largely pristine. In this satellite image, the red denotes such forests; these are almost as thick as those in the Amazon and Congo.

The thick forests in the Canadian Shield.

Winter still remains in this March scene in the Province of Manitoba just north of North Dakota. Dominating the scene is Winnipeg, appearing black against the light snow because of snow removal and melting in that large city. In the countryside, dark lines (cleared farm roads) block out squares that are one-mile sections (part of the Township-Range system of surveying) similar to those so prevalent in the Great Plains (the lowlands here are an extension of that physiographic unit into Canada). Lakes Manitoba (left-center edge) and Winnipeg (top center) are remnants of a once larger lake system that covered wide areas of the plains at the end of the Pleistocene ice age. The dark areas that extend over the right third of the scene are the western edge of the Precambrian Canadian Shield. Pine and spruce are the prevalent trees in this part of the Shield.

Winnipeg in the plains of Manitoba; the western edge of the Canadian Shield is to its east; the winter snow brings out the road pattern in the farmlands.

Winnipeg looks less foreboding in summer, as evident in this image which brings out the city's location within extensive farmlands:

Manitoba, in an unusual Landsat rendition.

Now, a look at the border between the U.S. and Canada in eastern Montana. The borderline is sharply defined. Why? Not because of a fence but the result of different land use practices. The Americans have opened up the high plains to farming; the Canadians have left most of their side in its original state - grass-covered rolling swales.

Landsat full image of the U.S.-Canadian border in Montana.

A strange feature showed up in a Digital Globe image of "badlands" in Alberta. Erosion has carved into clay-rich sedimentary rocks leaving a bas-relief figure that remarkably resembles an Indian, complete with a warbonnet. See for yourself and judge its authenticity: is it manmade(?):

A natural 'sculpture' of a plains Indian's head in the badlands of Alberta.

The plains of Alberta contain two large cities - Calgary and Edmonton. The former is the oil capital of Canada. It lies less than 160 km (100 miles) from the east front of the Canadian Rocky Mountains (Rockies) which have constricted to a tectonic zone about 250 km wide. Banff and Lake Louise are famed resort towns in these mountains.

Panoramic view of Calgary and the Rockies to its west.
Space image extending from the Banff section of the Canadian Rockies to Calgary.

This satellite image shows parts of Alberta and British Columbia, including both Edmonton and Calgary. Lake Louise is a world-famed resort (located to the upper left of the Highway marker for Route 1 [lower center]). The Chateau Lake Louise and the sheer cliffs to its south are shown in the aerial view below:

Satellite image of parts of Alberta and British Columbia; the large range is the Canadian Rocky Mountains; Banff and Lake Louise are along Route 1; Jasper is along Route 14; the Purcell and Selkirk Mountains are crossed by Rt. 1 to the west of Lake Louise.
Lake Louise.

The rugged Canadian Rockies appear in this satellite image - transect across British Columbia, from the Great Plains to the Pacific Ocean.

Transect across the Canadian Rocky Mountains and Pacific Coast ranges.

To one traveling on the Canadian Pacific scenic railroad route, the mountains of western Canada appear continuous. But the Rockies blend in with the wide expanse of the Coast Ranges. This Radarsat image shows these mountains, here traversed by the Columbia River just north of the U.S. border.

Radar image of the inland extension of the Coast Ranges of western Canada

This next image is a HCMM nighttime image covering much of southwestern Canada (swath width = 715 km [447 miles]). Starting in the upper right with part of the Rocky Mountain Trench, the terrain passes through inland hills and the mountains of the Coast Ranges (the black is cold nighttime snow), part of the Inland Passageway, and the northern half of Vancouver Island. Underneath this night expression of topograpy lie many tectonic terranes (see Section 17).

HCMM thermal night image of much of the mountain terrains of British Columbia; the Coast Range is the dark mountains - the Columbia Mountains are further east..

The Jewel of western Canada is Vancouver, BC, now a full-fledged city built on the Delta of the Fraser River. Across from it is Vancouver Island, with its tourist-popular small city of Victoria. South are the Georgian Bay Islands that extend to the San Juan Islands of Washington State.

Satellite image of Georgian Bay and Vancouver, BC.

This is an aerial view of Vancouver:

Vancouvir.

Tundra again is typical of Canadian island surfaces well above the Arctic Circle. In this scene, the major land body is Melville Island, made up of Paleozoic sedimentary rocks and characterized by deep embayments that are valleys gouged out by continental glaciation of the Pleistocene, now occupied by the Arctic Sea which even in this July view is still completely frozen. Human life in this part of Canada�s Northwest Territories is limited to a few native villages (Eskimo types).

 Melville Island in northern Canada; the Arctic Sea is frozen at this time.

Now that we are in the Arctic, let's face a dilemma: Where to place Greenland in the grand scheme of the world's geography? Greenland is the largest island in the world, 2,176,000 square kilometers (the next largest, New Guinea, is only about 40 as large: the much larger Australia and Antarctica, while they look like huge islands, are arbitrarily designated "continents"). Greenland is considered part of North America and indeed it lies on the North American tectonic plate. Here is a map of Greenland in context with Canada (and Russia):

Map showing Greenland's location.

As seen from space by MODIS, Greenland is revealed to be almost entirely covered by an ice sheet or cap several kilometers thick:

Greenland from space.

Actually, there are small towns and settlements along the ice-free fringes of Greenland, as shown in this map:

Map of Greenland showing inhabited villages.

The total population of Greenland is about 73000. Here is a typical village, whose inhabitants live mainly by fishing:

A fishing village in Greenland.

The ice on Greenland contains about 6% of the freshwater on the Earth's land surface. But, as global warming proceeds, the amount of renewed ice has been diminishing as the cap also shrinks, exposing more land.

The shrinking ice on Greenland; the red areas denote parts of the cap experiencing diminished ice renewal.

The ice-free parts of much of Greenland are mountainous. Here is the northernmost mountain group (highest point nearly 2 kilometers above sealevel) on Earth, in a region of Greenland known as Peary Land (after the Arctic explorer, Richard Peary):

ASTER image of northern Greenland.

Now, we follow the birds in winter and journey southward into the Caribbean and thence to South America.

Source: http://rst.gsfc.nasa.gov/