The science behind climate change

Urban waste, natural disasters and global warming were at the forefront of the University of Waterloo’s (UW) third annual Interdisciplinary Centre on Climate Change, which ran from Mar. 10 to 11. On Friday, the student organized summit welcomed renowned geomatics engineer Wanglin Yan to speak during the lunch hour session.

Yan, originally from Japan, received his PhD in geomatics engineering from the University of Tokyo is 1992. Currently he is a professor and researcher at the University of Keio where he specializes in geoinformatics for urban and regional environments as well as planning for sustainable development.

Before introducing his topic Yan solemnly noted the recent natural disasters and
the magnitude of the devastation in his homeland of Japan and spoke to connections between increasing levels of earthquakes and tsunamis as a result of global warming.

Turning to the focus of his lecture, Yan began discussing the urban heat island (UHI) within the problem of climate change. Yan, describing UHIs, said“[It is] a phenomenon that causes the air temperature in urban areas to be higher than those in rural areas because of the energy expended in human activities within urban centres.” He went on to explain that the energy emitted is a result of cars, factories, air conditioners and reduced green and water space.

The identification of this phenomenon is relatively new, Yan told the audience. It is just starting to take off, he explained, because “it is a very expensive process so data collection is difficult.”

The technology used to study urban heat islands are called isotherm maps, which plot the different temperatures present across a given geographic area. More recently, satellite-based thermal remote sensing devices are being introduced as a technique to evaluate these heat islands.

The science is gaining importance as there is an increased presence of urban heat islands resulting from urban development. Yan explained that this needs to be paid close attention as it is a very real contributor to the global warming crisis around the world.

The focus of Yan’s research is Japan’s effort to combat rising urban temperatures. One way to “mitigate the effect of UHIs is to implement regulations surrounding the construction of high rise buildings in already large cities,” he said. He also identified efforts being made in Japan currently, such as more green space and parks, water space, solar radiation shielding and rooftop greenery.

Yan, through the University of Keio, is also involved in programs designed for fostering environmental leaders in Asia and Africa and is attempting to accomplish it by welcoming international students and offering post-graduate programs in environmental sustainability. In tackling the problem of climate change, Yan stressed, “Both a private and public approach is necessary.”

Urban Heat Islands

  • The result of energy emissions from cars, factories and air conditioners

  • They are attributed to increasing the affects of global warming

Measures to improving urban warming

  • Water retentive pavement

  • Reflective paints

  • Indoor ventilation

  • Photovoltaic cells

  • Expanding green space such as parks

  • Increased water space such as ponds

  • Solar radiation shielding

  • Rooftop greenery