As the global population grows past seven billion, our cities continue to expand, increasing the need for natural resources while simultaneously decreasing the supply.
Google’s Earth Engine team created these time-lapse maps to illustrate a few of the trends reshaping the world right now.
The above image shows development spreading out rapidly in Las Vegas, one of five cities in the U.S. to grow by more than 40% in population from 2000 to 2010. This occurred as a consequence of migration to America’s Southwest as well as part of the global movement from rural areas into cities.
As of 2010, more than half of all people on earth lived in an urban area. By 2030, six out of every 10 will live in a city, and by 2050, the ratio will increase to seven out of 10 people, according to the World Health Organisation. In terms of sheer numbers, the amount of people living in cities will almost double by 2050, increasing from approximately 3.4 billion in 2009 to 6.4 billion — 5.2 billion of whom will live in developing countries.
As cities expand, they face problems rounding up enough non-renewable resources like fresh water to support their population. Desert-based Vegas has continually struggled to find enough water, which the city has handled so far through extensive pipelines diverting water from the Colorado River, providing almost 90% of the city’s supply.
Gulf State Growth
Above, you’ll see Dubai’s coastal region explode in the early part of the 21st century with famous artificial islands, Palm Islands and The World.
The Gulf States overall have seen rapid urbanization, fuelled by massive oil and gas supplies.
The Gulf Cooperation Council, which includes the United Arab Emirates, Bahrain, Saudi Arabia, Oman, Qatar, and Kuwait, saw the population of its member countries more than double from 1990 to 2011, now at 46 million. From 1995 to 2011, their combined GDP per capita more than tripled. And currently, they export about 20 million barrels of oil every day, constituting 24% of total global production, according to the Al-Monitor.
But this unprecedented pace of development has lead to problems as well, with fear of financial bubbles and vulnerability to food and water shortages. And then there are the political concerns.
“[Gulf States] have some institutions like elected parliaments, semi-elected or nominated advisory councils, local assemblies, municipal councils, political associations, and private media. Yet in no case do any of these institutions shape significant national policies, and when they become too feisty they are usually shut down for a while,” writes Rami Khouri, a senior fellow at Harvard’s Belfer Center.
Bodies of Water Drying
Considered “one of the planet’s worst environmental disasters,” Kazakhstan’s Aral Sea, formerly one of the world’s four largest lakes, lost most of its volume by 2012. In the early 1900s, Soviet policymakers decided to irrigate the area, diverting freshwater supply from the lake. That, coupled with local climate changes, drove the problem.
While the Aral Sea doesn’t provide drinking water, its drying is a staggering example of a much larger problem. Currently, one third of the world’s rivers — groundwater for about 3 billion people — are going or gone, according to the World Preservation Foundation.
Already, water scarcity hounds 2.7 billion people — nearly 40% of the world’s population — for at least one month every year, whether they don’t have access to clean water or can’t afford it, according to the Water Footprint Network. And one billion, about one-sixth of the world’s population, face daily shortages, according to the foundation.
By 2025, however, 1.8 billion people will live in countries or regions, mostly in the Middle East and North Africa, with absolute water scarcity, according to the International Water Management Institute. These areas won’t have enough water irrigate their fields (threatening their food supply) or for other domestic, industrial, and environmental purposes.
Aside from the human toll, the drying of lakes and rivers releases the greenhouse gases carbon dioxide and methane into the air, potentially exacerbating climate change. Because of the water cycle, the world will also face more drought, upping the chances of wildfires, as well.
From 1984 to 2012, deforestation spread in Brazil at an epic rate. In fact, over the course of the last 50 years, 17% of Amazonian forests have disappeared, mostly due to conversion for cattle ranching, according to the World Wildlife Fund.
Forests cover 31% of the planet, and are home to more than 80% of the world’s known species . They also provide 1.6 billion people with food, fresh water, clothing, and traditional medicine. But 46 to 58 thousand square miles of forest are lost each year — about the equivalent to 36 football fields every minute, according to the fund.
The climate will suffer from these losses, too. Trees suck up the greenhouse gases that coal burning puts out. Burning trees emits greenhouses gasses, too, contributing to about 15% of the global total. Without trees, soil erodes, potentially causing landslides and other catastrophes. The decline of forests, which help to balance the amount of water in the atmosphere with water on land, also alters the water cycle.
The above GIF shows the proliferation of irrigation in Saudi Arabia. The green circles represent patches of new farming land. While irrigation has been a major global trend, recently, the flow of water stagnating, especially in countries with the most need. With population growing but water availability and undeveloped land for farming decreasing, the productivity of crops will become even more crucial.
Since the 80s, increased irrigation has continually lowered the global food price index, according to the International Water Management Institute. In 2005, about 300,000 hectares of land were irrigated. But in Asia, the practice has leveled-off and remains nearly absent in Africa, two areas that desperately need higher crop yields now and in the future.
Asia, which houses 70% of the world’s irrigated land, could meet one-third of future food requirements by upping irrigation systems and modernizing existing ones. And Africa, with the greatest number of people suffering from water scarcity and hunger, has only 5% of farming land irrigated — the lowest ratio of any country, according to the institute.
This GIF shows the Columbia Glacier in Alaska melting. Although the glacier advances and retreats, it has lost half of its total thickness and volume since the 1980s, according to NASA. Researchers measure glacial deficits using mass balance, or the difference between the accumulated snow during winter and the subsequent melting in warmer temperatures. A glacier losing more ice during summer than it gained in the winter is considered negative gain.
20 of the largest glaciers worldwide, from Alaska to the tip of South America to central Europe, are melting, according to the Intergovernmental Panel on Climate Change.
Between 1980 and 2011, glaciers around the world lost the water equivalent of 15.7 meters. That translates to slicing a roughly 17-meter-thick slab off the top of the average glacier and repeating that exercise worldwide, according to the National Oceanic and Atmospheric Association.
All of this water has to go somewhere and it often causes flooding, as seen recently in Alaska.
The data continues to show increasing ice loss, often considered absolute proof of global warming. Melting in these proportions also causes increases in sea level and flooding of low level areas. These glaciers also release greenhouse gasses that had been trapped in their ice and their loss causes changes to the local and global climate.
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