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: Carbonation in concrete infrastructure in the context of global climate change; A number of recent studies have identified and begun to quantify increased susceptibility of the infrastructure to climate change–induced carbonation of reinforced concrete. In this paper, the results of a study are presented which uses an updated empirical model to predict the diffusion coefficient of carbon dioxide (CO2) in concrete and thereafter, predict carbonation depths for a number of urban environments in the United States. Data from newer climate forecasts from the 5th Intergovernmental Panel on Climate Change assessment report are used to generate predictions for carbonation depths in four U.S. cities of varying geographic and climatic conditions (Los Angeles, Houston, Chicago, New York City). Results confirm that carbonation depths will increase in the future because of climate change. The magnitude of the increase is dependent on the climate-change scenario considered and the geographic location of the city. Whether or not the increases will require building code changes to increase concrete cover or improve concrete quality will be dependent on actual construction practices for the city in question., Peer-reviewed article, Published. Received: January 05, 2015; Accepted: July 30, 2015; Published online: October 28, 2015.

: Carbonation in concrete infrastructure in the context of global climate change; In Part1 of this paper, a carbonation model was developed and experimentally veriﬁed which was able to forecast carbonation depth of a concrete specimen considering varying ambient temperature, humidityand CO2 concentrations. Part 2 of the paper applies the carbonation diffusion/reaction model developed in Part 1 to predict the effects of global climate change on the carbonation of concrete. Climate scenarios were formulated and combined with the model for two major Canadian cities, Toronto and Vancouver. Results show that for undamaged and unstressed concrete, climate change will signiﬁcantly affect carbonation progress. The model showed that for unloaded, non-pozzolanic concrete, ultimate carbonation depths in Toronto and Vancouver could be up to 45% higher. For in-service structures under load, the rates of deterioration are likely to be even faster. This is a cause for concern, and much further effort must be devoted to fully understand these phenomena., Peer-reviewed article, Published. Received 18 October 2011; Revised 21 April 2012; Accepted 24 April 2012; Available online 10 May 2012.

: Carbonation in concrete infrastructure in the context of global climate change; There is nearly unanimous consensus amongst scientists that increasing greenhouse gas emissions, including CO2 generated by human activity, are affecting the Earth’s climate. Increasing atmospheric CO2 emissions will likely increase the rates of carbonation in reinforced concrete structures.In this paper, the serviceable life, from construction through to cracking due to carbonation induced corrosion of concrete infrastructure is considered in various cities throughout the world. It was concluded that global climate change will affect the progression and will result in much higher ultimate carbonation depths in the long term., Peer-reviewed article, Published. Received 23 May 2012; Revised 1 October 2012; Accepted 9 November 2012; Available online 25 December 2012.

: A greenhouse gas emissions inventory and ecological footprint analysis of Metro Vancouver residents’ air travel; Ecological Footprint Analysis (EFA) at the city or regional scale does not typically include air travel due to a lack of readily available data. However, knowing the “load” placed on nature by various lifestyle choices, including air travel, is essential if we hope to enable society to live sustainably within ecological limits. This paper provides methods for including air travel in urban EFA, in a manner that is accessible to those that are interested in the complexities of urban sustainability. Our goal is to use the case of the Vancouver Metropolitan region to illustrate two methods in such a way that they can be replicated or adapted for use in other cities and regions. We found that the greenhouse gas emissions of air travel by Metro Vancouver residents for 2006 is between 1,191,070 and 1,402,420 tonnes of carbon dioxide equivalent (tCO2e). The resulting ecological footprint is between 287,030 and 337,980 global hectares (gha), or between 0.136 and 0.160 gha/capita. The dedicated carbon sink required to neutralize the carbon dioxide emissions from Metro Vancouver residents’ air travel alone is equivalent to twice the land area of the region (283,183 hectares)., Peer-reviewed article, Published. Received: July 15, 2013 ; Accepted: September 16, 2013 ; Online Published: September 27, 2013.

: Storage and the shift to low carbon energy; This work looks at the impact of assumptions made regarding efficiency of storage systems used with variable energy resources and how this applies to a solar PV installation. To find the optimal storage system to work with the cyclic solar output, a linear optimization model is implemented using OSeMOSYS. With 100% efficient, free storage, with no capacity restrictions, it is possible to get down to almost 5 GW of required solar installed capacity, but it requires 1.1 TWh of 100% efficient storage. Existing pumped hydro storage facilities have efficiencies between 70 and 80%, which increase these numbers to 7 GW and 1.2 TWh. With a storage model based on the worlds largest pumped hydro facility between 20 and 25 GW of installed solar capacity are required plus between 15 and 30 GWh of storage capacity to meet the 1 GW load. The capital infrastructure required to allow a solar installation to meet that of a baseload plant is therefore around an order of magnitude larger than what is commonly assumed. A shift away from fossil fuels to renewable/variable energy resources will require more infrastructure than indicated by simply considering the capacity factor of the energy source., Peer-reviewed article, Published. Manuscript received September 30, 2014; revised January 18, 2015.