Climatic changes.

A comprehensive study is conducted to evaluate global sea levels for trends and variations due to climate change and variability by using non-parametric methods. Individual and coupled effects of inter-annual ENSO, decadal PDO, multi-decadal AMO, and quasi-decadal NAO on sea levels are evaluated. Combined influences of different phases (cool or warm) of PDO, AMO, and NAO influences and ENSO are also evaluated. The results from this study showed that sea level at 60% of the sites is increasing with time with all four oscillations impacting global sea levels. AMO warm phase individually and PDO warm combined with La-Niña phase contribute to higher sea levels throughout the world. Trends and variations in sea levels are noted to be spatially non-uniform. Understanding and quantifying climate variability influenced variations in sea levels and assessment of long-term trends enables protection of coastal regions of the world from sea level rise.

This study identified factors that affect climate change risk perception in a
community college class. The purpose of this research was to determine if students were
more influenced by cultural cognition (political affiliation) or science comprehension.
Students in an undergraduate level environmental science and biology class were
evaluated, using an online survey, for science comprehension level, political affiliation
and risk perception at the beginning and end of each course. Data were analyzed to
determine improved scientific literacy and any variation in risk perception. The research
found that science comprehension did not contribute significantly to increased risk
perception and that political affiliation or political views had a more significant effect on
risk perception.

The concept of Intensity Duration Frequency (IDF) relationship curve presents crucial design contribution for several decades under the assumption of a stationary climate, the frequency and intensity of extreme rainfall nonetheless seemingly increase worldwide. Based on the research conducted in recent years, the greatest increases are likely to occur in short-duration storms lasting less than a day, potentially leading to an increase in the magnitude and frequency of flash floods. The trend analysis of the precipitation influencing the climate variability and extreme rainfall in the state of Florida is conducted in this study. Since these local changes are potentially or directly related to the surrounding oceanic-atmospheric oscillations, the following oscillations are analyzed or highlighted in this study: Atlantic Multi-Decadal Oscillation (AMO), El Niño Southern Oscillation (ENSO), and Pacific Decadal Oscillations (PDO). Collected throughout the state of Florida, the precipitation data from rainfall gages are grouped and analyzed based on type of duration such as short-term duration or minute, in hourly and in daily period. To assess statistical associations based on the ranks of the data, the non-parametric tests Kendall’s tau and Spearman’s rho correlation coefficient are used to determine the orientation of the trend and ultimately utilize the testing results to determine the statistical significance of the analyzed data. The outcome of the latter confirms with confidence whether there is an increasing or decreasing trend in precipitation depth in the State of Florida. The main emphasis is on the influence of rainfall extremes of short-term duration over a period of about 50 years. Results from both Spearman and Mann-Kendall tests show that the greatest percentage of increase occurs during the short rainfall duration period. The result highlights a tendency of increasing trends in three different regions, two of which are more into the central and peninsula region of Florida and one in the continental region. Given its topography and the nature of its water surface such as the everglades and the Lake Okeechobee, Florida experience a wide range of weather patterns resulting in frequent flooding during wet season and drought in the dry season.

A confounding factor for sea level rise (SLR) is that it has a slow, steady creep,
which provides a false sense for coastal communities. Stresses caused by SLR at today’s
rate are more pronounced in southeastern Florida and as the rate of SLR accelerates, the
exposure areas will increase to a point where nearly all the state’s coastal infrastructure
will be challenged.
The research was conducted to develop a method for measuring the impact of
SLR on the City of West Palm Beach (City), assess its impact on the stormwater system,
identify vulnerable areas in the City, provide an estimate of long-term costs of
improvements, and provide a toolbox or strategies to employ at the appropriate time. The
assessment was conducted by importing tidal, groundwater, topographic LiDAR and
infrastructure improvements into geographic modeling software and performing analysis
based on current data. The data revealed that over $400 million in current dollars might
be needed to address stormwater issues arising from SLR before 2100.