That giant sucking sound you hear is from the steady flow of jobs from downtown to the suburbs and points beyond.

During the first decade of this century, roughly one of every five jobs that had been in Buffalo’s central business district disappeared, according to a new report from the Brookings Institute.

Some of those jobs went away entirely, as the region muddled through two recessions. But some of those jobs moved out to the suburbs – and beyond, with the portion of the metro area that’s more than 10 miles away from downtown standing out as the only segment of the Buffalo Niagara region that actually gained jobs from 2000 to 2010.

In short, the heart of the Buffalo Niagara economy is steadily shifting away from downtown Buffalo and moving toward the suburbs.

Brookings researchers call that shift “job sprawl,” and it’s not a good thing for shrinking areas, like the Buffalo Niagara region.

“It’s not just about the number of jobs,” said Elizabeth Kneebone, the report’s author and a fellow at the Brookings Metroploitan Policy Institute in Washington, D.C. “The location of those jobs matters, too.”

And in the Buffalo Niagara region, the location of those jobs is changing.

The heart of the local job market has always been in that ring that runs between three to 10 miles from downtown, and that’s still the case. About half of the region’s jobs were packed into that ring in 2000, and despite the steep job cuts at the auto plants in the Town of Tonawanda and Hamburg during the decade, along with other manufacturers in that belt, it still was home to 51.3 percent of the region’s jobs in 2010.

But downtown has been struggling. While 21.6 percent of the region’s jobs were within three miles of downtown in 2000, just 18.1 percent were within the central business district in 2010 as office work migrated to the suburbs and the remaining retail downtown shriveled.

And most concerning, the part of the region that has turned into a magnet for jobs is the area that’s in the farthest ring, between 10 and 35 miles from downtown. That ring, which stretches from North Tonawanda to Lake Ontario in the north; from Depew to Batavia in the east and from Hamburg to Dunkirk in the south, actually added 3.7 percent more jobs during the 10-year period. As a result, 30.6 percent of all local jobs now are located in that far-flung ring, up from 28.3 percent at the turn of the century.

Kneebone said the Buffalo Niagara region has plenty of company in seeing the shift in jobs toward the outermost ring of suburbia. Nationally, the share of jobs located at least 10 miles from downtown (43 percent) had grown to be nearly double the share of jobs located downtown (23 percent).

“Almost every major metro area experienced a decline in the share of jobs located downtown,” she said. “This happened in every type of market,” both the booming ones and the ones, like Buffalo, that were struggling during the 2000s.

The type of job also plays a role in the shift. Retail jobs tend to be focused away from downtowns, and so is factory work, which tumbled by nearly 40 percent during the decade. “Every major industry saw a shift of jobs outward,” Kneebone said.

The good news is that the Great Recession brought the shift to a virtual halt. The share of jobs in each of the three rings in 2010 were very close to what they were in 2007, before the recession hit.

But that doesn’t mean the shift won’t resume when the economy picks up steam. And it’s why the Western New York Regional Economic Development Council, which is playing a growing role in charting the region’s economic development strategy, has made stopping sprawl a major priority, by encouraging what they call “smart growth” policies.

That means cleaning up brownfields so that land can be used again productively, rather than leaving vast pockets of vacant, poisoned property in prime locations within Buffalo and the first-rung suburbs. The council also has come up with a scorecard to measure the “smart growth” qualities of projects and is backing a handful of projects to improve the infrastructure in downtown Buffalo.

The plan for the “Buffalo Billion” envisions “dense, mixed-use, mixed-income communities with excellent transportation and virtual connections” as one of the keys to developing a productive and sustainable regional economy.

“Smart growth is good economic development,” said James J. Allen, the executive director of the Amherst Industrial Development Agency.

That’s because sprawl is expensive, requiring costly investments in new infrastructure, such as roads and utilities, as businesses push farther and farther away from the city core. It also puts low-income workers at a big disadvantage, because many of the jobs at those new developments likely won’t be on public transportation routes, making it difficult – if not impossible – for workers without cars to get to them, Kneebone said.

That’s why Amherst officials have been working with the Niagara Frontier Transportation Authority to try to come up with ways to expand bus service in the town. That’s an easier sell when business activity is concentrated within a particular area – development officials call it density – than when it’s spread throughout the hinterlands.

“We need in-fill development. We need to take underdeveloped properties and make them denser. Why do we need to do it? Because it’s good for public transportation,” Allen said. “We have to figure out how to get public transportation throughout Amherst,” Allen said. “The people who work in Amherst can’t always afford to live in Amherst.”

And as jobs push outward, so does the demand for housing from workers who want to live closer to their employers so they can shorten their commutes. The flip side is that, with the region’s population declining, that only weakens the demand for housing near the downtown area and exacerbates the problem of vacant and crumbling housing in the city.

Redevelopment is a big part of the solution to sprawl, too. The Lakeside Commerce Center just south of the Tifft Nature Preserve is a great example of that, with a barren industrial wasteland that sat unused for decades being converted into an industrial park that now is home to companies that otherwise might have picked a site on undeveloped property in the suburbs.

“The real challenges arise when you see this decentralization take place in a more spread out, diffuse way,” Kneebone said. “It’s harder to serve spread-out jobs with transit effectively. It also has implications for low-income residents.”