A rapid global climate change is set to hit New Delhi hard. This was revealed by the State of World Population 2007, released by the United Nations Fund for Population Activities (UNFPA) on Wednesday.

The report said cities that grew rapidly over the decades with unimaginative architecture and gave up the traditional patterns adapted to local climate conditions would face hard time in wake of the climate change.

The report singled out New Delhi as one of the cities that will be hard hit as climate change takes place.

Quoting from a recent report of the Inter-Governmental Panel on Climate Changes, UNFPA study said "cities in drier regions, such as New Delhi in India and Karachi in Pakistan will be particularly hard hit".

Several reasons were given as to why this urbanisation drive may not cope up with the climate change. According to the report "as villages grow into towns and then into cities, their average temperature increases 2 to 6 degree Centigrade above that of the surrounding countryside".

Elaborating the looming danger points, the report stated that changes in temperature and precipitation could spread diseases like malaria, dengue and yellow fever, in previously unaffected areas and encourage it in areas already affected.

Delhi, which has already had records of water shortage, will share an additional burden of climate change as it dramatically affects water supplies with danger of water-borne diseases.

The part of report dealing with urbanisation and climate change, revealed that "the use of new architecture and urban forms, new materials and innovations such as air-conditioning have driven up both energy costs and cities' contributions to greenhouse gas emissions".

The report has appealed to the Government to resolve the problem of slum dwellers and also elaborate on strategies to deal with the problem of housing for the poor. However, the study warned that urbanisation was not a solution in itself and has to be dealt cautiously.

"Swelling slum population is prone to hunger, poor sanitation and health facilities, dreaded diseases, widening gap between rich and poor and absence of safety nets."

Union Urban Development Minister S Jaipal Reddy said urbanisation, being bi-product of industrialisation, "is here to stay, it is irreversible and imminently desirable".

Reddy said the Jawaharlal Nehru National Urban Renewal Mission has been launched with an aim to improve urban infrastructural facilities in the country.

With better job opportunities and higher wages, States like Maharashtra and Tamil Nadu were witnessing rapid urbanisation in comparison to Bihar and Assam which are least urbanised, a UN report said.

"Urbanisation is happening due to natural rate of population growth statically coupled with the increase in the rate of migration in these States," UNFPA (India) representative Nesim Tumkaya said after the release of the report - State of World Population 2007.

According to the report, rate of natural growth in urban areas is much higher in comparison to rural areas. In 2004, the rate of growth in urban area was estimated to be 1.77 per cent against 1.38 per cent in villages.

In India, Tamil Nadu tops the list of the major States with 43.9 per cent of the total population living in the urban areas followed by Maharashtra (42.4 per cent) and Gujarat (37.4 per cent), according to the report. On the contrary, only 10.5 per cent of the population are residing in urban areas in Bihar while 12.7 per cent population in Assam and 15 per cent population in Orissa are living in urban areas, the report said quoting Census 2001.

Dwelling on the "pull" and "push" of migration, the report said poverty and hunger, marginal land holdings, lack of basic amenities and unemployment force the people to move from rural to urban areas, expecting better income and job opportunities and standard of living