From Yale University
Growth of cities endangers global environment
New Haven, Conn.—The explosive growth of cities worldwide over the next two decades poses significant risks to people and the global environment, according to a meta-analysis published today in PlosOne.
Researchers from Yale, Arizona State, Texas A&M and Stanford predict that by 2030 urban areas will expand by 590,000 square miles—nearly the size of Mongolia—to accommodate the needs of 1.47 billion more people living in urban areas.
“It is likely that these cities are going to be developed in places that are the most biologically diverse,” said Karen Seto, the study’s lead author and associate professor in the urban environment at the Yale School of Forestry & Environmental Studies. “They’re going to be growing and expanding into forests, biological hotspots, savannas, coastlines—sensitive and vulnerable places.”
Urban areas, they found, have been expanding more rapidly along coasts. “Of all the places for cities to grow, coasts are the most vulnerable. People and infrastructure are at risk to flooding, tsunamis, hurricanes and other environmental disasters,” said Seto.
The study provides the first estimate of how fast urban areas globally are growing and how fast they may grow in the future. “We know a lot about global patterns of urban population growth, but we know significantly less about how urban areas are changing,” she said. “Changes in land cover associated with urbanization drive many environmental changes, from habitat loss and agricultural land conversion to changes in local and regional climate.”
The researchers examined peer-reviewed studies that used satellite data to map urban growth and found that from 1970 to 2000 the world’s urban footprint had grown by at least 22,400 square miles—half the size of Ohio.
“This number is enormous, but, in actuality, urban land expansion has been far greater than what our analysis shows because we only looked at published studies that used satellite data,” said Seto. “We found that 48 of the most populated urban areas have been studied using satellite data, with findings in peer-reviewed journals. This means that we’re not tracking the physical expansion of more than half of the world’s largest cities.”
Half of urban land expansion in China is driven by a rising middle class, whereas the size of cities in India and Africa is driven primarily by population growth. “Rising incomes translate into rising demand for bigger homes and more land for urban development, which has big implications for biodiversity conservation, loss of carbon sinks and energy use.”
The paper, “A Meta-analysis of Global Urban Expansion,” can be viewed on the PlosOne website at http://dx.plos.org/10.1371/journal.pone.0023777.
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
What the ### is PlosOne?
“Half of urban land expansion in China is driven by a rising middle class”
And the brand spanking new but empty apartments and condos are for what?
It’s true that cities tend to be unfortunately located, in a way, on the most attractive land. That’s where people start settlements, obviously. However, reducing rural populations has a number of up sides for “the environment”. It also, it turns out, slashes the energy cost of feeding and housing any given number of people. Locally grown and sourced foodstuffs, e.g., are much more fuel-intensive per pound delivered to the customer than even very remotely grown and transported ones.
The findings really say one thing: “We think this is about to happen, and we must put a stop to it!” Otherwise I see no purpose to the exercise, because no mention of adaptation is made. And lo and behold, the hasty mention-in-passing of “carbon sinks” in the last sentence of the last paragraph. Oops! Almost forgot to mention it! Had to make sure it got a favorable review!
Note also, that their review was of “peer-reviewed studies”. Whew! Sure glad they were careful to avoid Greenpeace, huh?
What the **** has man been doing since Adam was a boy???? We have it as an art form using prime agriculture land for suburban expansion here in my state, where around 75% of state’s population living in one city..
…and just in time for THIS regurgitation from CNN:
http://www.cnn.com/video/#/video/international/2011/07/20/road.durban.sanergy.cnn?iref=allsearch
“Researchers from Yale, Arizona State, Texas A&M and Stanford predict that by 2030 urban areas will expand by 590,000 square miles—nearly the size of Mongolia—to accommodate the needs of 1.47 billion more people living in urban areas.”
This works out to about 2,500 population per square mile or about 925 per square kilometer., population densities seen in exurbs in the US but densities hardly seen in most of the world, particularly in the developing world where much of the world’s urban growth will take place. Average urban growth will more likely be at densities of 10,000 per square mile or even more if population density patterns seen in China and India mean anything. If this is the case, then the expansion of urban areas will be on the order of one-fourth of the figure stated above.
Another point is that most of these people will be moving from lower density rural areas to higher density urban areas, meaning that the population densities in many rural places around the world will likely fall. Many of these areas will revert to a more “natural” environment and it is entirely possible, if not likely, that the increase in “natural” environment in rural areas will exceed the loss of “natural” environment due to urban expansion. Would be most interested in seeing if this study looks into the potential gain in “natural” environment in rural regions over the study period.
Universities are strange places inhabited by stranger people. Kangaroos in Australia are in greater numbers now than ever before, at least certain species are. They are the species that adapted to man and man’s pastures and watering systems. In some places roos are in plague proportions and can eat out a farmers crops long before the crops reach maturity. Same with other species, such as rats, that benefit from man. A niche is developed and a species adapts to fill it. Humans are no different. Human population cannot increase beyond the carrying capacity of the land. A balance is reached at some point and the population will plateau. It is already noted that as societies become wealthier and more educated they tend to have less children. Maybe it’s simply the fact that modern diets and medicine ensure the survival of the next generation so there is no need to over produce.
None of these researches sees the obvious example of China itself. China has a large population density but for all intents is self sufficient in food. Europe produces more than it consumes as does Australia and the Americas. India feeds itself. The only continent in difficulty is Africa and that arises from poor governments rather than poor soils.
Once again we see a bunch of intelligent people who are not aware of the real world around them. Instead of going to uni just open your eyes and observe. Then we wouldn’t have to listen to alarmist drivel.
“whereas the size of cities in India and Africa is driven primarily by population growth. “Rising incomes translate into rising demand for bigger homes and more land for urban development”
I am glad to see that incomes in Africa are rising given that the emphasis on bio-fuels is causing African children to die of starvation by the thousand …
Mankind is using less that 20% of the land area on this planet – http://en.wikipedia.org/wiki/Land_use_statistics_by_country
Seems like yet another scare mongering attempt. I am old enough to remember when research grants were given for looking at ways to make life better for everyone.
London [quite a pleasant sprawling city] is 160 sq miles with a population of 8,000,000
Mongolia is 604,000 sq miles
You can get 3775 Londons in Mongolia x 8000000 pop = 30 200,000,000 or over 30 billion.
In fact the whole world [7 billion] could live in 875 Londons requiring 140,000 sq miles which is around half the size of Texas and leave the rest of the world completely empty.
If you replaced London with a denser packed city it would be much higher.
Again these people talk utter tosh.
PS I’ve just woken up and this took me 3 minutes so any arithmetical corrections welcome, but you get the principle.
So what environments are NOT “sensitive and vulnerable?” Pure bedrock? A lava lake? Yeah, right, we’re running out of “elbow room” and we’re taking all the valuable “hoof and paw room” from all the darling fuzzy animals – better get a nice fat grant, quick! We’ll solve this like we always do with the awesome efficiency of Government Planning! Hurray!
Ugh.
Perhaps it’s like the Penn State paper on alien destruction – see update – it could be down to “carelessness and inexperience”. Maybe IPCC AR4 should be checked, too.
Now, that’s, er, quite an insight. So, human beings, those well known social animals, like to live in human-habitable areas, near other human beings. Remarkable.
So, dare we hope the uber-environmental crowd will be showing us ordinary folk the way forward by building PlosOveVille, say, in the middle of a desert? Can we have a webcam or two there please, to help us learn?
I think there’s an error in that 3% number for world urban population. According to Wikipedia there are 205 urban areas with 2,000,000 or more. If the average is near the median there are about 700,000,000 people, or 10% of the world population in that 205. There are 796 urban areas with 500,000 or more.
Depending on where you draw the “urban” line the number could be in the 15% to 30% range.
Why when reading studies like this do I get the impression that to save the enviromant we must cull man? (I’m getting to old to apologies for my un-PC use of the word ‘man’).
Hmm in Aus this present unelected cluster, are doing their damndest to make any coastal living…except the gross tourist areas, and the rich waterfront marinas, simply unavailable, to the extent of forcing sales. then they tell us we should stop farming and plant it all back to trees.
our transport water power, especially since they sold it to privateers etc is all sadly lacking maintenance and volume to cope now. so dislocating people to already jampacked inefficient cities is the way to contain us?
I think not!
Funny!
“It is likely that these cities are going to be developed in places that are the most biologically diverse,”
Like Dubai?
David Schofield – the 160 sq miles you use for London seems small – on Wikipedia – it reports area as 607 sq miles. So 1000 Londons in Mongolia or capacity of 8 Billion. Wide awake or not, the point you make is nonetheless still valid. These people talk utter tosh.
All the US has to do is quit sponsoring flood insurance:
“The promise was national flood insurance. It made my house and my neighbors’ homes possible. After all, no bank will give you a mortgage unless you have insurance.
Private insurance companies were reluctant to sell insurance to those of us who build on the edges of oceans, and were they to offer it, they’d charge an arm and a leg to cover the risk. But this wasn’t a problem for me, because you offered to insure my house. I know you didn’t do it personally, but you, as a taxpayer, are the guarantee behind federal flood insurance. Should a big storm wipe out half the coast, you’ll cover our losses — up to a quarter-million dollars. Thanks — we appreciate it — but what a dumb policy.
The subsidized insurance goes to affluent homeowners on both coasts — from Malibu Beach, where movie stars live, to Kennebunkport where the Bush family has a vacation home, to Hyannisport, where the Kennedy family has a summer home, to the Hamptons, where I bought my house.
The insurance premiums were a bargain. The most I ever paid was a few hundred dollars. Federal actuaries say if the insurance were realistically priced, it would cost thousands of dollars. Why should the government guarantee water’s-edge insurance? Why should the government be in this business at all? ”
http://abcnews.go.com/Business/Insurance/story?id=94181
Once the space aliens get here, problem solved.
Do you think the warmists are teetering on the edge, about to go over?
Seems the real problem is we have too many people, and some need to go. Any volunteers?
Here in Michigan, Detroit is showing the way toward the new “urban environment.” Vast tracts are being “returned to nature.” One can see wild flora springing from the abandoned center of what was once a highly-concentrated human habitat. In fact, Detroit has led the state and the nation in showing what environmental responsibility means. Each year the CO2 output of this region has declined.
Let’s hear it for visionaries!
http://4.bp.blogspot.com/-k0iknMwVAOA/TkKzsjXhDEI/AAAAAAAABEc/ve2W4oLq-ng/s1600/deadcoop.jpg
So. It really is all my fault. It’s all your fault, too.
Sorry, just testing… I’m trying to put myself in “their” shoes, you know.
Think I’ll stick with who I am. It must really suck to be “concerned”.
No more guilt trips, I promise.
Jim says:
August 20, 2011 at 4:30 am
“The subsidized insurance goes to affluent homeowners on both coasts — from Malibu Beach, where movie stars live, to Kennebunkport where the Bush family has a vacation home, to Hyannisport, where the Kennedy family has a summer home, to the Hamptons, where I bought my house. The insurance premiums were a bargain. The most I ever paid was a few hundred dollars. Federal actuaries say if the insurance were realistically priced, it would cost thousands of dollars. Why should the government guarantee water’s-edge insurance? Why should the government be in this business at all? ”
Well Jim, I just paid my flood insurance. $1054 for the year and I live 1 mile as the crow flies from the beach with an elevation is 13 ft (pretty high for coastal Florida). My property is valued at $120K and there are tens of thousands of properties like mine so your statement about “subsidized insurance goes to affluent homeowners” isn’t true for the majority. Flood insurance is also available for those who live near any body of water that could flood including inland lakes and rivers.
FYI my insurance premium is low because of a little known grandfather clause. At the time of construction, prior to 1992, my house was built above the base flood elevation which was 11 ft back then. After Hurricane Andrew, FEMA needed to replace the losses they paid out so they remapped the coastal areas and raised the base flood elevations. In my area they put it at 15 ft. Now the grandfather clause says that if your house was above the base flood elevation at the time it was built, subsequent increases of base flood elevations do not apply and you keep your flood designation that was assigned at the time of construction. My property was originally designated as Flood Zone D and was then changed to Flood Zone AE which would more than triple my premiums. Newer construction pays the higher premium which is well above the “few hundred dollars” you claim to paid.
David Schofield says:
August 20, 2011 at 1:20 am
To extrapolate on David.
You could transplant the whole 7 billion humans now living on the planet to a mega complex in a friendly climate environment like the north east cost of Australia and then use the rest of the world’s agricultural areas to feed that population. Heck you could probably just use the rest of the agricultural land in Australia to do this.
Of course this would all rely on a nice utopian version of human co operation.
Most likely expanding cities will expand around the current location of said cities. I doubt developers will go out of their way to hit environmentally sensitive areas. As an offset, the rural population keeps diminishing as the young move into urban areas and the old die, creating large interconnected areas with low human populations for many species to migrate to.
Logistics. The issue is not how many people you can cram into a given area, but rather the logistical strain of supporting that many in a small area. At some point the logistics will break down.