Historical differences in temperature between urban and non-urban areas in Puerto Rico

Abstract

Previous studies of the influences of land use/land cover changes (LULCC) on the climate of continental areas have provided a basis for our current understanding of LULCC impacts. However, continental climates may not provide complete explanations or answer specific scientific questions for other regions, such as small tropical-maritime dominated islands. Here we present a detailed analysis of temperature change over the past century for the tropical island of Puerto Rico, using an approach that accounts for internal climate variability and spatial resolution issues and assesses the degree to which some of this change might be related to urban development. Long-term weather data, digital maps, geographic information systems (GIS) and statistical analysis were used to detect and assess differences between urban and non-urban temperature records. Strong evidence of a relationship linking temperature magnitudes to local urban development was detected, and the analysis suggests that urbanization has increased minimum, maximum and average temperatures by 0.5 ∘ C in the warmest regions to 2 ∘ C in the coolest regions. The results also show that the magnitude of temperature impacts depends on the contextual ecology or environment where the development has occurred. Temperature differences between urban and non-urban areas are higher in colder and wetter microclimates than in dryer warmer ones, and were less pronounced for minimum temperature than for maximum temperature. However, because the levels of impacts are based on data that had some prior adjustment intended to control for urban signals, they represent minimum estimates of the impacts of land use on temperature in Puerto Rico.

Short-Term Precipitation and Temperature Trends along an Elevation Gradient in Northeastern Puerto Rico

“…A larger p value cutoff of a 5 0.10 was chosen for this entire study over the more traditional 0.01 or 0.05 because many of the climate trend studies covering PR (Burrowes et al 2004;Greenland and Kittel 2002;Heartsill-Scalley et al 2007;Stephenson et al 2014;Torres-Valcárcel et al 2014;Vose et al 2005) have used a t test and fit a least squares trend line, which exaggerates the significance of the trend, reporting a reduced p value, for non-Gaussian datasets.…”

“…A study by Torres-Valcárcel et al (2014) suggests that, if the positive trend in precipitation is not simply part of a climate cycle, it may be due to increasing urban development and a higher sensitivity or response to urban impacts in wetter areas of PR such as the northeast. A study by Torres-Valcárcel et al (2014) suggests that, if the positive trend in precipitation is not simply part of a climate cycle, it may be due to increasing urban development and a higher sensitivity or response to urban impacts in wetter areas of PR such as the northeast.…”

Teleconnections between ENSO and rainfall and drought in Puerto Rico

“…Torres‐Valcárcel et al . (, ) used a similar methodology in previous climate studies in Puerto Rico. However, in this study, regional and seasonal data were aggregated by averaging monthly totals of all existing stations and data points from the same region and same season at a given time, ignoring missing values.…”

“…Although the global climate may change, changes are not necessarily linear or symmetrical and may not uniformly impact every place on Earth in the same direction and magnitude. Although climate studies at small scales can help understand climate phenomena at larger scales, climatological studies of tropical islands remain limited (Torres-Valcárcel et al, 2015). Most assessments of climate change focus on regional and global impacts and thus may lack enough detail to help local efforts in policy and decision making.…”

Translating land-use science to a museum exhibit

“…Ecologists have mostly focused on how the vegetation composition of secondary forest varied as a result of different land uses (Aide, Zimmerman, Pascarella, Rivera, & Marcano-Vega, 2000; Thompson et al, 2002). Others have analyzed how these patterns of change have shaped stream water quality (Uriarte, Yackulic, Lim, & Arce-Nazario, 2011), bird populations (Acevedo & Restrepo, 2008), channel morphology (Clark & Wilcock, 2000), and climate variables (Torres-Valcárcel, Harbor, Torres-Valcárcel, & González-Avilés, 2015). Social scientists have evaluated the socio-economic drivers of change and its theoretical implications (Rudel, Perez-Lugo, & Zichal, 2000).…”