Poverty concentration has resurfaced in the U.S., and disproportionately Hispanic and black populations reside in high-poverty ghettos, slums and barrios. The concentration of poverty instigates urban violence, police-community tension and the enduring legacy of racism.

"Architecture of Segregation: Civil Unrest, the Concentration of Poverty and Public Policy," a report published Aug. 9, stated approximately 62 percent of Hispanics and 65 percent of blacks live in poverty in the city of Syracuse, New York, which increased by 13 percent and 22 percent, respectively, since 2000. According to The Century Foundation, small cities like Syracuse have grown 12.6 percent since 2000, while the nation's largest metro areas have grown by less than 2 percent. Alongside that growth, the number of neighborhoods struggling with 40 percent or more families living in extreme poverty tripled between 2000 and 2013.

According to the report, we are now witnessing a nationwide return of the concentration of poverty, which is racial in nature. The expansion exists in the form of high-poverty ghettos and barrios. The report states, "these neighborhoods are not the value-free outcome of the impartial workings of the housing market. Rather, in large measure, they are the inevitable and predictable consequences of deliberate policy choices."

The concentration of poverty is also about the "special organization" of poverty, which is conceptually distinct from poverty measured at the individual level. Addressing the root causes of urban violence, police-community tension and the enduring legacy of racism, as well as the origin of urban slums and what sustains them, is a matter of examining characteristics of neighborhoods of extreme deprivation and the trends in the population.

There's been a dramatic increase in the number of high-poverty neighborhoods, and there are 6.6 million more people living in high-poverty ghettos, slums and barrios than there were in 2000, the numbers nearly doubling. Despite popular belief, the Great Recession isn't solely responsible for the increases in poverty concentration. More than 1-in-6 poor Hispanics and 1-in-4 poor blacks live in extreme poverty, compared to 1-in-13 poor whites. Even before the financial crisis and the subsequent recession, there was a historic increase in the number of high-poverty neighborhood with non-white residents being more numerous. Furthermore, poor children are more likely to live in high-poverty neighborhoods than poor adults. Comparably, white poor children are less likely to live in high-poverty neighborhoods than white poor adults. Blacks and Hispanics in high-poverty ghettos and barrios increased from 3 to 5 million and 2.2 to 4.3 million, respectively.

Poverty concentration also increased among Hispanics, but only after the recession began. The report found that poor blacks are three times more likely and poor Hispanics are twice more likely to reside in a neighborhood with a poverty rate of 40 percent or more than a poor white person following the recession. Of the nation's 100 largest areas, the city of Syracuse has the highest level of poverty concentration among blacks and Hispanics. Syracuse is followed by Detroit, Rochester, Milwaukee, Fresno, Buffalo, and Cleveland, which also experienced substantial increases in Hispanic concentration of poverty since 2000.

Additionally, Philadelphia's Hispanic concentration has high concentrations of poverty, and McAllen, Texas has seen a decline.

After the dramatic decline in concentrated poverty between 1990 and 2000, poverty has re-concentrated. Detroit is an extreme example of high-poverty trends, "borderline" neighborhoods and financial crisis. Luckily, most poor people-regardless of racial or ethnic group-don't live in high-poverty neighborhoods. These are individuals who don't have to carry the "double disadvantage" of having poverty-level family income while living in an area dominated by poor families with similar social problems.

There's also a 90 percent increase in the number of immigrants in high-poverty neighborhoods, which is the same as the overall increase. Thus, immigrants have contributed to increases in high-poverty areas. However, the concentration of poverty among the foreign-born poor is virtually identical to concentration among the native-born poor. Immigrants tend to cluster more in linguistic and cultural enclaves, and residents in those neighborhoods tend to be better-off than native-born individuals in high-poverty neighborhoods. Interestingly, the presence of immigrants actually has a moderating effect on the concentration of poverty.