Climate Change

The Earth's climate is not static, and over millions of years it has progressed through many cycles of warm and cool periods. The Earth is currently in the midst of a natural warming cycle, but in this case human activities are giving the natural climate cycle a not-so-gentle push. The scientific community has over the last few decades arrived at a consensus that the activities of humans are significantly altering atmospheric conditions through the emission of greenhouse gases (GHGs) that create an insulating layer over the Earth. Greenhouse gases produced by human activity are actually a small portion of those produced by natural processes worldwide, but the marginal increase since the start of the industrial revolution has been enough to push worldwide GHG levels beyond the capacity of "carbon sinks" such as our forests and oceans (themselves greatly degraded by humans) to absorb them from the atmosphere.

The Kyoto Protocol of 1997 identified six greenhouse gases that contribute most to global warming: carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), sulfur hexafluoride (SF₆), hydrofluorocarbons (HFCs), and perfluorocarbons (PFCs). Because CO₂ is by far the most prevalent of these, climate change is often discussed in terms of carbon ("carbon footprint," "carbon sinks," and "carbon neutral" just to name a few). All greenhouse gases are typically measured in terms of their CO₂ equivalencies (CO₂e).

Source: http://en.wikipedia.org/wiki/File:Carbon_Dioxide_400kyr.png

How does our work contribute to, or help ameliorate, global warming?

PB as a company has pledged to reduce its carbon footprint. That is, it has considered what GHG emissions it is responsible for as a company (operational energy for offices, employee business travel, employee commuting, and office waste) and has identified several tactics to reduce these emissions:

• Office-based green teams that streamline office recycling processes, encourage waste reduction, and promote alternative commuting means
• Energy saving equipment and occupancy censors
• Purchase of GHG reductions by others, or "offsets."

Research by the Carbon Trust and Imperial College demonstrates that a 60 percent reduction in carbon emissions can be achieved by 2050 using a mixture of energy efficiency, renewable sources of electricity, replacing coal and oil with lower carbon fuels such as gas and the use of hydrogen as a fuel.

PB's work has great potential to reduce GHG emissions beyond our own office doors. In the decades to come, it will be incumbent on our clients in the transportation, building, power and water sectors to do the heavy lifting of GHG reductions, and PB's expertise will help them develop techniques and strategies to get that done.

We will also help our clients predict, prepare for, and adapt to the effects of climate change that we now know are unavoidable, such as sea-level rise, intensified storms, or prolonged drought.

PB Climate Change Community of Practice [must be on PB's network, requires login]