Newfoundland and Labrador

California

Kansas

Nebraska

Oklahoma

Oregon

Texas

Québec

None

<p>A map of North America showing typical surface weather patterns. Dark lines indicate troughs shown in western region of Oregon, Newfoundland and Labrador, California, Texas, Oklahoma, Kansas, and north of Cuba in North Atlantic Ocean.</p>

<p>An elongated area of relatively low atmospheric pressure, often associated with fronts</p>

Trough

North America

NOAA

Acid Rain

African Languages

Agricultural Regions

Anthropogenic Biomes

Approximate Form and Extent of Outcrop of Carbonate Rocks

Aquifers: Distribution and Recharge

Areas Affected by Acid Rain

Areas Affected by Trypanosomiasis

Areas at Risk of Soil Degradation

Average Annual Precipitation

Average Annual Snowfall

Average Distribution of Dew Point Temperatures, January

Average Distribution of Dew Point Temperatures, July

Average Number of Hail Storms

Average Number of Tornado Incidences per Year (U.S.)

Bantu Migrations

Barren or Sparsely Vegetated Areas

Biomes

British Conquest of India

British Empire, Early 1920s

Caribbean Languages

Chinese Empires

Climate Zones

Cold Front

Colonial Possessions, 1914

Continental Shelf

Core Diamond Mining Areas

Days with Heavy Fog

Deforestation: Net Loss, 2000-2015

Deserts and Desertification Risk

Distribution of Calcium Carbonate in Modern Surface Sediments

Distribution of Neritic (Nearshore) and Pelagic (Open Ocean) Sediments

Drought Risk

Drug Cultivation and Production Regions

Early Sub-Saharan States and Empires

Earthquake Hazard Areas (U.S.)

Ecological Regions: Level 1 Regions

Ethnic and Cultural Regions

Ethnic Diversity

Ethnic Groups (Iraq and Iran)

European Settlement Expansion

Forest Types, 1900

Former Soviet Republics

Former Warsaw Pact Members

General Area of Sedimentary Formations Favorable to Oil

Geographic Areas Under Dispute

Geology Rock Type

Global Mean Temperature, January

Global Mean Temperature, July

Global Surface Warming: Best-Case Projections

Global Surface Warming: Worst-Case Projections (IPCC)

Global Surface Warming: Worst-Case Projections (NASA)

Global Temperature Change

Groundwater Salinization

Habitat Fragmentation

Herder's Environment

Human Occupation

Indigenous Languages

Insolation

Lake Desiccation

Land Cover

Language Families

Languages - Russian Domain

Language Subfamilies

Large Chinese Communities

Latin America, 1650

Latin America, 1830

Lightning Frequency

Major Drainage Basins

Major Foreign Enclaves and Exclaves

Major Hearths

Major Iron-Producing Areas in North America

Major Karst Regions

Major Landforms

Major Manufacturing Regions

Major Soil Orders

Major Territorial Acquisitions (U.S.)

Malaria Risk Areas

Mangrove swamps

Marine Sediment Thickness

Mean Sea-Surface Temperature

Muslim Populations

National Parks

Native American Culture Areas

Natural Gas Supply Areas

Ocean Bathymetry

Ocean Circulation Sinks

Ocean Climate Zones

Oil Shale or Tar Sands

Oil Slicks (1990s)

Original Tillers' Environment

Peak Drought Record, 2016 (U.S.)

Peak Drought Record (U.S.)

Petroleum and Natural Gas Production

Political Units, 1914

Political Units, 1950

Populist Governments Since 2000

MapMaster 3

Trough