Decarbonising cities and the role of remote sensing for planning, developing, and monitoring low carbon precincts

Although space technologies are extremely useful to environmental researchers, the contribution that they make in monitoring city greenhouse gas emissions is limited to measuring those emissions. Standing alone, satellite technology is incapable of advancing the goal of decarbonisation. This goal will be achieved only if municipalities find local methodologies that reduce carbon emissions. Once these methodologies are implemented, the satellite measurements can demonstrate if remedial actions are succeeding. This paper is based on current work done jointly with municipalities to ascertain where, within urban systems, emissions originate and how they can ultimately be reduced. It both presents remote sensing as helpful to decarbonising precincts and discusses the impact of certain carbon mitigating strategies. Considerable potential exists for the use of satellite measurements and remote sensing to assist local authorities in planning, mapping, modelling, and developing low carbon infrastructure. The challenge is converting satellite-derived data into the kind of information that allows precinct communities, together with other stakeholders, to make decisions that result in low carbon outcomes at the precinct scale. 1. Cities’ facilitation of an emerging green economy: an introduction The population of cities is growing at an unprecedented rate. Fifty percent of the world‟s people now live in urban areas, and this figure is rising progressively. Demographers expect that by 2050, 5.3 billion people, or 70% of the human race, will reside in cities [1]. Left uncontrolled, this rapid urban growth threatens to contribute to many environmental disasters—massive habitat loss and species extinction, depletion of the Earth‟s finite resources, such as potable water and precious minerals, extreme pollution and build-up of waste, as well as soaring carbon emissions and global warming. However, „smart‟ development of our cities promises to minimise humankind‟s impact on the environment, for example high density living and urban infill can decrease pollution by making it more convenient for people to walk and take public transport. Because it is imperative for our survival that humanity live harmoniously on Earth, cities must work to become part of the solution through attention to their design, function, and governance. Society has a pressing responsibility to wean itself from dependence on high-consumption, highcarbon economies and to accept a low-consumption, low carbon existence. Fortunately, this change can be made without jeopardising peoples‟ lifestyles; in fact it can actually improve humankind‟s social well-being [2]. Decarbonising, which is part of this process, will involve redesigning cities as low carbon centres with circular patterns of urban resource flows that foster community resilience. The restructuring of urban pathways with low carbon infrastructure networks will involve cities collaborating with international, national, and local governments, non-governmental organisations, 35th International Symposium on Remote Sensing of Environment (ISRSE35) IOP Publishing IOP Conf. Series: Earth and Environmental Science 17 (2014) 012009 doi:10.1088/1755-1315/17/1/012009 Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Published under licence by IOP Publishing Ltd 1 research institutes, universities, local communities, and the private sector. Space agencies can also play an important role in this process. 2. International agreement on decarbonised development In 2009, at the 15 th Conference of the Parties (COP-15) of the United Nations Framework Convention on Climate Change, global leaders meeting in Copenhagen made a significant political agreement to work together towards establishing international cooperation and action for the decarbonisation of development. The Copenhagen Accord (CHA) emphasises both that “deep cuts in global emissions are required . . . so as to hold the increase in global temperature below 2 degrees Celcius . . . and that a low-emission development strategy is indispensable to sustainable development [3].” Since Copenhagen, the Intergovernmental Panel on Climate Change (IPCC) has reinforced this agreement by stressing the important role that cities can play in achieving the overall goal of reducing global carbon emissions by facilitating decarbonised development and encouraging the emerging green economy [4]. 3. Cities’ contribution to carbon emissions As major centres of carbon intensive production and resource use, the world’s expanding cities account for a large proportion of rising global carbon emissions. However, discrepancies exist in the reporting of exactly how much they contribute, with some reports overstating emission figures. On the one hand, World Energy Outlook 2008 claims that cities are responsible for 71% of worldwide emissions; on the other, the Clinton Climate Initiative states that they contribute 80% [5]. Even more contradictory, the IPCC avers that cities are more likely responsible for between 30% and 40% of global carbon dioxide (CO2) emissions [6]. This inconsistency reveals not only a degree of uncertainty about the precise quantity of carbon emissions but also a lack of agreement about with whom and where the responsibility lies for their production. For instance, factories located in semi-rural areas outside a city’s boundaries are often the source of stationary energy consumed by city dwellers for their domestic and commercial purposes. However, these emissions are often excluded from the calculation of a city’s total carbon footprint. Obviously, in order to determine the appropriate carbon mitigating actions required to moderate, reduce, or prevent the growth of carbon emissions, it is imperative to identify and measure the output of key sources for which a city is responsible. 4. Space agencies’ measurement of urban carbon emissions Space agencies are helping resolve some of the ambiguity surrounding the contribution of cities to global carbon emissions. Satellite technology is being deployed to assess city greenhouse gas emissions so that these emissions can be measured and monitored more accurately. NASA’s Jet Propulsion Laboratory Megacities Carbon Project is measuring multi-year emission trends of carbon dioxide, methane (CH4), and carbon monoxide (CO) attributed to several megacities and selected major sectors. After this pilot project’s three year trial, NASA in coordination with its international partners, such as the Japanese Space Agency, may expand it to other cities [7]. Remote sensing, satellite technology is extremely useful not only for measuring city greenhouse gas emissions but also for gaining an initial perspective on the impact that these growing metropolises are having on global carbon emissions. However, the challenge is to account for those emissions generated outside a city’s boundaries for which a city is nevertheless responsible and which should be included in calculating its carbon footprint. These activities in space could be extended further to assist cities with calculating the emissions inherent within the totality of their energy, water, and waste systems and with providing guidance on which portions of carbon emissions they should be responsible for attempting to mitigate. 4.1. Calculating carbon in urban systems 35th International Symposium on Remote Sensing of Environment (ISRSE35) IOP Publishing IOP Conf. Series: Earth and Environmental Science 17 (2014) 012009 doi:10.1088/1755-1315/17/1/012009