CONTEXT: With rapidly expanding urban regions, the effects of land cover changes on urban surface temperatures and the consequences of these changes for human health are becoming progressively larger problems. OBJECTIVES: We investigated residential parcel and neighborhood scale variations in urban land surface temperature, land cover, and residents’ perceptions of landscapes and heat illnesses in the subtropical desert city of Phoenix, AZ USA.

Despite the global trend in urbanization, little is known about patterns of biodiversity or provisioning of ecosystem services in urban areas. Bee communities and the pollination services they provide are important in cities, both for small-scale urban agriculture and native gardens. To better understand this important ecological issue, we examined bee communities, their response to novel floral resources, and their potential to provide pollination services in 25 neighborhoods across Chicago, IL (USA).

Land use change is one of the main stress factors on ecosystems near urban areas. We analysed land use dynamics within Xochimilco, a World Heritage Site area in Mexico City. We used satellite images and GIS to quantify changes in land use/land cover (LULC) from 1989 to 2006 in this area, and a Markov projection model to simulate the impact of different management scenarios through to 2057. The results show an alarming rate of urbanisation in 17 years. LULC change runs in one direction from all other land use categories towards urban land use.

Today, more than half the world’s population lives in cities. By 2030, it is projected that 6 in 10 people will be urban dwellers. By 2050, the figure will have risen to 6.5 billion people; representing two-thirds of all civilization. Taking into account the increasing rural to urban migration and the rapid growth of cities in the developing world, it is clear that cities face a myriad of problems that may hinder planned growth and development.

• There is an accute lack of well-located urban housing that is adequate, secure, and affordable. The global affordable housing gap is currently estimated at 330 million urban households and is forecast to grow by more than 30 percent to 440 million households, or 1.6. billion people, by 2025.

The New Urban Agenda represents a shared vision for a better and more sustainable future – one in which all people have equal rights and access to the benefits and opportunities that cities can offer, and in which the international community reconsiders the urban systems and physical form of our urban spaces to achieve this.

In September 2015, the United Nations Sustainable Development Summit adopted a new framework to guide development efforts between 2015 and 2030, entitled “Transforming our world: the 2030 Agenda for sustainable development”.1

As we turn the page on MDGs to SDGs, the unprecedented proliferation of slums and informal settlements, and a chronic lack of adequate housing, continues to be amongst the major challenges of urbanization. Slums, informal settlements and inadequate housing remain the visible manifestations of poverty and inequality in cities. Inadequate housing complements the measurement of slums, particularly in the developed world, in order not to leave anyone behind.

Cities function in an efficient, equitable and sustainable manner only when private and public spaces work in a symbiotic relation to enhance each other. Public space generates equality, however in the past decades it has been drastically been reduced. Inadequate, poorly designed, or privatized public spaces generate exclusion and marginalization.

A defining feature of many of the world’s cities is an outward expansion far beyond formal administrative boundaries, largely propelled by the use of the automobile, poor urban and regional planning and land speculation. A large proportion of cities both from developed and developing countries have high consuming suburban expansion patterns which often extend to even further peripheries. Cities need to accommodate new and thriving urban functions such as transportation routes, etc. as they expand.

Geoffrey Payne outlines five fundamental propositions that are key to his understanding of tenure issues and policy options.

These are:

1) That access to affordable land with adequate security of tenure and associated rights is a pre-condition for realising the goal of adequate housing and poverty reduction;

After natural disasters, governments often relocate vulnerable urban communities in the name of humanitarian relief. But urban communities rarely welcome such relocation, since it frequently exacerbates their daily challenges or creates new risks. Indeed, resettlement after a disaster is often another form of eviction. This briefing discusses the situation in Chennai, where state and local authorities have been building resettlement tenements on inland marsh areas using centrally sponsored schemes for affordable housing.