Reference Terms
from Wikipedia, the free encyclopedia
Topographic map
Topographic maps, also called contour maps, topo maps or topo quads, are maps that show topography, or land contours, by means of contour lines. Contour lines are curves that connect contiguous points of the same altitude (isohypse). In other words, every point on the marked line of 100 m elevation is 100 m above mean sea level.
Related Stories
1
2
Earth & Climate News
July 13, 2026
July 12, 2026 Scientists discovered that extreme deep-sea pressure squeezes valuable nutrients out of sinking organic particles, providing an unexpected food source for ocean microbes. The finding could rewrite our understanding of both deep-ocean ecosystems and ...
July 12, 2026 Why do beaches today have seashells from clams and snails instead of brachiopods? A new study suggests the answer lies in Earth's greatest mass extinction, when warming oceans and falling oxygen levels wiped out animals that couldn't adapt. Species ...
July 11, 2026 Two striking Asian praying mantis species that have rapidly spread across Europe have now been officially classified as invasive, raising new concerns about their impact on native wildlife. Boosted by climate change and urban environments, these ...
July 10, 2026 A newly discovered underwater volcanic eruption north of Papua New Guinea is unfolding in one of the world's most poorly mapped ocean basins. Satellites have spotted steam plumes, ash, thermal hotspots, and huge floating pumice rafts, suggesting ...
July 10, 2026 A next-generation pesticide designed to kill crop pests may also be interfering with the reproductive health of bumblebees. Researchers discovered that low-dose exposure to sulfoxaflor changed gene activity, especially in tissues involved in ...
July 9, 2026 Oak trees keep absorbing carbon dioxide long after their annual growth has ended, revealing that photosynthesis and wood production are not as closely linked as scientists once believed. The finding could reshape forecasts of how much carbon forests ...
July 8, 2026 Ocean temperature patterns appear to act as a natural brake on the global spread of drought, preventing vast areas of the planet from drying out simultaneously. Researchers found that shifting climate cycles create regional drought hotspots while ...
July 5, 2026 Scientists have uncovered a hidden weakness beneath the Pacific Ocean that helps explain why Japan’s catastrophic 2011 earthquake and tsunami became so devastating. By drilling deeper into the ...
July 3, 2026 Scientists have uncovered new evidence that fireworks can pollute both the air and water in ways that extend beyond the visible smoke. The findings show that leftover debris, fine particles, and airborne chemicals may affect ecosystems and increase ...
July 3, 2026 A new study found that not all geoengineering ideas are created equal. Brightening marine clouds over the eastern Pacific could dramatically weaken the El Niño cycle, triggering major changes to ...
July 2, 2026 A pioneering climate scientist is challenging a U.S. government report that cited his research while reaching what he says is the exact opposite conclusion. Benjamin Santer and his colleagues say ...
June 28, 2026 Researchers have discovered that beneficial soil bacteria give plants an unexpected survival advantage in salty soils. Instead of helping plants keep salt out, the microbes stimulate the production of lignin, a natural compound that strengthens ...
Latest Headlines
updated 12:56 pm ET
July 10, 2026 Mount Etna has long puzzled geologists because it doesn't fit any of the three classic ways volcanoes are thought to form. A new study suggests it may instead be fueled by ancient pockets of magma ...
June 29, 2026 Scientists have finally confirmed the origin of the mysterious Silverpit Crater beneath the North Sea. New evidence shows that an asteroid about 160 ...
June 28, 2026 Hawaii researchers are giving old fishing nets and recycled plastic a second life by mixing them into asphalt roads. Early tests found these roads didn't release more plastic particles than standard ...
June 27, 2026 A surprising ecological makeover unfolded when mountain lions began frequenting a small preserve south of San Francisco. Deer activity dropped, plants recovered, and shifts among predators like ...
June 26, 2026 A new study reveals that goldfish can do far more than survive in the wild—they can fundamentally reshape freshwater ecosystems. Researchers found they cloud water, damage food webs, and hurt ...
June 24, 2026 A Pacific-wide tsunami triggered by a magnitude 8.8 Kamchatka earthquake gave scientists their first detailed satellite view of a major tsunami in motion. The observations revealed unexpected wave ...
June 23, 2026 Researchers found that highly drug-resistant bacteria from hospitals are also resistant to glyphosate, a commonly used weedkiller. The discovery ...
June 23, 2026 A cave in New Zealand has yielded fossils from a lost ecosystem that existed about 1 million years ago, including a possible flying ancestor of the kākāpō. The discovery reveals that volcanoes and ...
June 22, 2026 Trees planted to protect farmland from wind may not be the biodiversity boost many assume. In Japan’s wetland farming landscapes, shelterbelts benefited some birds but sharply reduced grassland and ...
June 21, 2026 Freshwater lakes across North America and Europe are becoming noticeably browner, reducing underwater visibility and reshaping fish populations. Research found that several popular sport fish, ...