With a mainland surface area of 2,780,400 km2 (1,073,518 sq mi), Argentina is located in southern South America, sharing land borders with Chile across the Andes to the west; Bolivia and Paraguay to the north; Brazil to the northeast, Uruguay and the South Atlantic Ocean to the east; and the Drake Passage to the south; for an overall land border length of 9,376 km (5,826 mi). Its coastal border over the Río de la Plata and South Atlantic Ocean is 5,117 km (3,180 mi) long.
Argentina's highest point is Aconcagua in the Mendoza province (6,959 m (22,831 ft) above sea level), also the highest point in the Southern and Western Hemispheres. The lowest point is Laguna del Carbón in the San Julián Great Depression Santa Cruz province (−105 m (−344 ft) below sea level, also the lowest point in the Southern and Western Hemispheres, and the seventh lowest point on Earth)
The northernmost point is at the confluence of the Grande de San Juan and Río Mojinete rivers in Jujuy province; the southernmost is Cape San Pío in Tierra del Fuego province; the easternmost is northeast of Bernardo de Irigoyen, Misiones and the westernmost is within Los Glaciares National Park in Santa Cruz province. The maximum north–south distance is 3,694 km (2,295 mi), while the maximum east–west one is 1,423 km (884 mi).
Some of the major rivers are the Paraná, Uruguay—which join to form the Río de la Plata, Paraguay, Salado, Negro, Santa Cruz, Pilcomayo, Bermejo and Colorado. These rivers are discharged into the Argentine Sea, the shallow area of the Atlantic Ocean over the Argentine Shelf, an unusually wide continental platform. Its waters are influenced by two major ocean currents: the warm Brazil Current and the cold Falklands Current.
Argentina is divided into seven geographical regions:
- Northwest, a continuation of the high Puna with even higher, more rugged topography to the far-west; the arid precordillera, filled with narrow valleys or quebradas to the mid-west; and an extension of the mountainous Yungas jungles to the east.
- Mesopotamia, a subtropical wedge covering the western Paraná Plateau and neighboring lowlands enclosed by the Paraná and Uruguay rivers.
- Gran Chaco, a large, subtropical and tropical low-lying, gently sloping alluvial plain between Mesopotamia and the Andes.
- Sierras Pampeanas, a series of medium-height mountain chains located in the center.
- Cuyo, a basin and range area in the central Andes piedmont, to the west.
- Pampas, a massive and hugely fertile alluvial plain located in the center east.
- Patagonia, a large southern plateau consisting mostly of arid, rocky steppes to the east; with moister cold grasslands to the south and dense subantarctic forests to the west.
Argentina is a megadiverse country hosting one of the greatest ecosystem varieties in the world: 15 continental zones, 3 oceanic zones, and the Antarctic region are all represented in its territory. This huge ecosystem variety has led to a biological diversity that is among the world's largest:
- 9,372 cataloged vascular plant species (ranked 24th)
- 1,038 cataloged bird species (ranked 14th)
- 375 cataloged mammal species (ranked 12th)
- 338 cataloged reptilian species (ranked 16th)
- 162 cataloged amphibian species (ranked 19th)
Although the most populated areas are generally temperate, Argentina has an exceptional amount of climate diversity, ranging from subtropical in the north to polar in the far south. The average annual precipitation ranges from 150 millimetres (6 in) in the driest parts of Patagonia to over 2,000 millimetres (79 in) in the westernmost parts of Patagonia and the northeastern parts of the country. Mean annual temperatures range from 5 °C (41 °F) in the far south to 25 °C (77 °F) in the north.
Major wind currents include the cool Pampero Winds blowing on the flat plains of Patagonia and the Pampas; following the cold front, warm currents blow from the north in middle and late winter, creating mild conditions. The Sudestada usually moderates cold temperatures but brings very heavy rains, rough seas and coastal flooding. It is most common in late autumn and winter along the central coast and in the Río de la Plata estuary. The Zonda, a hot dry wind, affects Cuyo and the central Pampas. Squeezed of all moisture during the 6,000 m (19,685 ft) descent from the Andes, Zonda winds can blow for hours with gusts up to 120 km/h (75 mph), fueling wildfires and causing damage; between June and November, when the Zonda blows, snowstorms and blizzard (viento blanco) conditions usually affect higher elevations.