Rings of Time
Nigel Grenier
St Thomas Aquinas
Floor Location : J 031 L

Understanding climate change is one of the most important environmental challenges that humans face today. I wanted to undertake a project to see if I could learn about climate change and understand some of the tools that scientist use to study this problem. I also wanted to know how climate is related to vegetation and how it affects tree growth. My project uses tree rings to compare with climate data. This scientific method known as dendro-climatology can be a valuable tool for scientists to predict past climates and to predict how climate change will affect tree growth in the future. I expected a decrease in tree ring width in drought conditions because there is a correlation between tree ring growth and climate (precipitation, temperature). I completed this project because I know that climate is a limiting factor in tree growth.rn In this study I took core samples from Ponderosa Pine trees in Penticton, B.C. I measured the width of tree rings, de-trended them and compared these with annual precipitation and spring and growing season temperatures to see their relationship. I inputted the data into an excel database to correlate and graph the data.rn Once graphed, I noticed that ring widths decreased steadily as the trees aged. The reason for this is that as a tree radius gets larger the newer ring widths although quite small actually represent a much larger area of new tissue. When this cycle had been removed I found that climate factors such as precipitation and temperature do have an effect on tree growth. Early spring and moderate summer temperatures as well as an abundance of precipitation result in favorable growing conditions. I was surprised to find that changes in precipitation were not more significant. There are many other unaccounted variables that are difficult to measure that must be affecting tree growth.rn