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Showing posts from November, 2020

The Human Impact on the Earth's Surface

There is no agnosticism that human activity has changed the planet, but to what extent? As it turns out, approximately 95 percent of the planets' surface is experiencing some form of transformation, with 85 percent having signs of multiple types of human influence. The map below by data scientist Hannah Ker describes humanity's transformation of terrestrial land ecosystems. The map is based on the Global Human Modification of Terrestrial Systems data, which traces the physical extent of thirteen anthropogenic stressors across 5 categories. Human settlement: population density, built‐up areas Agriculture: cropland, livestock Transportation: major roads, minor roads, two tracks, railroads Mining and energy production: mining, oil wells, wind turbines Electrical infrastructure: powerlines, nighttime lights The researcher gathered all these factors and scaled their impact from 0 to 1. Then, he mapped these effects. The land's surface was organized into cells of one square

Forests in the world

 According to the FAO, forests cover about 4 million square kilometers (or 15.1 sq mi), about 30 planets of the Earth’s land surface. Europe accounts for one-fourth of the whole forest area, accompanied by South America and North America among world regions. South America is the continent with the highest forest cover percentage, while Asia is the continent with the lowest rate of forest cover. Forests at various latitudes and elevations form different biomes: boreal, temperate, tropical forests. published a world atlas of different forest biomes. Map of Needleleaf forests Needleleaf forests grow mostly in territories that have long, harsh winters. These forests spread over Canada and northern Europe. Scarce needle-leaf forests grow in some warmer territories. For example, the Southeastern U.S. states have extensive groves of pines, such as Pinus taeda and Pinus palustris. Evergreen broadleaf forests Evergreen broad-leaved forests grow in the subtropical, tropical, and e

There are 400 trees for every human on earth

The world distribution and extent of forest trees are necessary to our knowledge of the biosphere. Scientists provide the first spatially continuous world map of forest tree density. This map shows that the global amount of trees is about three trillion, an order of magnitude greater than the earlier estimate. Of these trees, around 1.30 trillion live in tropical and subtropical forests, with 0.74 trillion in boreal areas and 0.66 trillion in moderate regions. Biome-level trends in tree density display climate and topography's influence in controlling local tree densities at more precise scales and humans' overwhelming effect across most countries. According to research over fifteen billion trees are cut down each year, and the world number of trees has fallen by about 46 percent since the origin of human civilization.

A Global Breakdown of Greenhouse Gas Emissions by Sector

 In several decades, greenhouse gases have grown at unprecedented rates due to global growth and resource consumption. Total emissions reached 49.4 billion tonnes of CO₂ equivalents. The graphic below from Our World in Data reveals the significant sectors where these emissions originate.  The global greenhouse emissions can be approximately traced back to 4 general categories: energy, agriculture, industry, and waste. Sources of greenhouse gases emissions Energy Use - 73.2% Agriculture, Forestry, and Land Use - 18.4% Industrial processes - 5.2% Waste - 3.2%