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- Title
- Remote sensing of evapotranspiration using automated calibration: development and testing in the state of Florida.
- Creator
- Evans, Aaron H., Obeysekera, Jayantha, Zhang, Caiyun, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
- Abstract/Description
-
Thermal remote sensing is a powerful tool for measuring the spatial variability of evapotranspiration due to the cooling effect of vaporization. The residual method is a popular technique which calculates evapotranspiration by subtracting sensible heat from available energy. Estimating sensible heat requires aerodynamic surface temperature which is difficult to retrieve accurately. Methods such as SEBAL/METRIC correct for this problem by calibrating the relationship between sensible heat and...
Show moreThermal remote sensing is a powerful tool for measuring the spatial variability of evapotranspiration due to the cooling effect of vaporization. The residual method is a popular technique which calculates evapotranspiration by subtracting sensible heat from available energy. Estimating sensible heat requires aerodynamic surface temperature which is difficult to retrieve accurately. Methods such as SEBAL/METRIC correct for this problem by calibrating the relationship between sensible heat and retrieved surface temperature. Disadvantage of these calibrations are 1) user must manually identify extremely dry and wet pixels in image 2) each calibration is only applicable over limited spatial extent. Producing larger maps is operationally limited due to time required to manually calibrate multiple spatial extents over multiple days. This dissertation develops techniques which automatically detect dry and wet pixels. LANDSAT imagery is used because it resolves dry pixels. Calibrations using 1) only dry pixels and 2) including wet pixels are developed. Snapshots of retrieved evaporative fraction and actual evapotranspiration are compared to eddy covariance measurements for five study areas in Florida: 1) Big Cypress 2) Disney Wilderness 3) Everglades 4) near Gainesville, FL. 5) Kennedy Space Center. The sensitivity of evaporative fraction to temperature, available energy, roughness length and wind speed is tested. A technique for temporally interpolating evapotranspiration by fusing LANDSAT and MODIS is developed and tested. The automated algorithm is successful at detecting wet and dry pixels (if they exist). Including wet pixels in calibration and assuming constant atmospheric conductance significantly improved results for all but Big Cypress and Gainesville. Evaporative fraction is not very sensitive to instantaneous available energy but it is sensitive to temperature when wet pixels are included because temperature is required for estimating wet pixel evapotranspiration. Data fusion techniques only slightly outperformed linear interpolation. Eddy covariance comparison and temporal interpolation produced acceptable bias error for most cases suggesting automated calibration and interpolation could be used to predict monthly or annual ET. Maps demonstrating spatial patterns of evapotranspiration at field scale were successfully produced, but only for limited spatial extents. A framework has been established for producing larger maps by creating a mosaic of smaller individual maps.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004194, http://purl.flvc.org/fau/fd/FA00004194
- Subject Headings
- Climatic changes, Environmental sciences -- Remote sensing, Evapotranspiration -- Measurement, Geographic information systems, Remote sensing -- Data processing, Spatial analysis (Mathematics)
- Format
- Document (PDF)
- Title
- Seagrass (Thalassia testudinum) Nutrient Recycling in Florida Bay, a Carbonate-Dominated Shallow Estuary.
- Creator
- Rosch, Kara Baca, Koch, Marguerite, Florida Atlantic University
- Abstract/Description
-
Nitrogen (N) and phosphorus (P) senescent leaf retention, as a measure of resorption, and the subsequent decay of senescent leaves, roots and rhizomes were examined for the dominant tropical seagrass species, Thalassia testudinum, across a nutrient gradient in Florida Bay. Leaf nutrient loss while still attached to the short shoot, from both resorption and decay, was highest at the nutrient-rich (88% P; 51% N) compared to nutrient-poor site ( 49% P; 25% N). High nutrient loss rates by...
Show moreNitrogen (N) and phosphorus (P) senescent leaf retention, as a measure of resorption, and the subsequent decay of senescent leaves, roots and rhizomes were examined for the dominant tropical seagrass species, Thalassia testudinum, across a nutrient gradient in Florida Bay. Leaf nutrient loss while still attached to the short shoot, from both resorption and decay, was highest at the nutrient-rich (88% P; 51% N) compared to nutrient-poor site ( 49% P; 25% N). High nutrient loss rates by attached leaves (0.37-2.5 mg P and 6.5-34 mg N m^-2 d^-1) represented significant recycling (46-87% P and 17-48% N) oftotal estimated external nutrient loads to the bay. In contrast, senescent leaf, rhizome and root nutrient loss rates were > 1 00-fold lower than intact leaves. In tropical /subtropical estuaries dominated by T testudinum, seagrasses may be acting as nutrient pumps, translocating high porewater nutrients to the overlying waters and promoting phytoplankton blooms in the bay.
Show less - Date Issued
- 2007
- PURL
- http://purl.flvc.org/fau/fd/FA00000822
- Subject Headings
- Estuarine ecology--Florida--Florida Bay, Seagrasses--Florida--Florida Bay, Stream ecology--Methodology, Climatic changes
- Format
- Document (PDF)
- Title
- Magnitude of Middle Miocene warming in North Pacific high latitudes: stable isotope evidence from Kaneharaia (Bivalvia, Dosiniinae).
- Creator
- Oleinik, Anton E., Marincovich, Louie, Jr., Barinov, Konstantin B., Swart, Peter K.
- Abstract/Description
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The Middle Miocene Climatic Optimum (MMCO) at ~ 16 Ma was the warmest interval during the Neogene. The peak of the MMCO in the North Pacific is marked by the appearance of the bivalve genus Kaneharaia (Bivalvia, Dosiniinae) in the high-latitude regions of Kamchatka and Alaska (55 –65°N). Specimens of Kaneharaia sp. were collected from two early middle Miocene high-latitude localities in the North Pacific – the Sea urchin Horizon of northwestern Kamchatka and the Narrow Cape Formation of...
Show moreThe Middle Miocene Climatic Optimum (MMCO) at ~ 16 Ma was the warmest interval during the Neogene. The peak of the MMCO in the North Pacific is marked by the appearance of the bivalve genus Kaneharaia (Bivalvia, Dosiniinae) in the high-latitude regions of Kamchatka and Alaska (55 –65°N). Specimens of Kaneharaia sp. were collected from two early middle Miocene high-latitude localities in the North Pacific – the Sea urchin Horizon of northwestern Kamchatka and the Narrow Cape Formation of Alaska. Middle Miocene Kaneharaia specimens were incrementally sampled for oxygen and carbon stable isotope records of seasonality. Results were compared with stable isotope profiles constructed for two Recent species of Dosinia from subtropical waters.
Show less - PURL
- http://purl.flvc.org/fcla/dt/210410
- Subject Headings
- Biogeography--North Pacific Ocean, Mollusks, Fossils--North Pacific Ocean, Sediments (Geology)--North Pacific Ocean, Paleoclimatology--Miocene, Climatic changes--North Pacific Ocean
- Format
- Document (PDF)
- Title
- Joint probability analysis of precipitation and streamflow extremes.
- Creator
- Lin, Chia-hung., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
This thesis focuses on evaluation of joint occurrence of extreme precipitation and streamflow events at several hydrologic structures in South Florida. An analysis of twelve years storm events and their corresponding peak streamflow events during wet and dry season including annual peaks considering two seasons was performed first. Dependence analysis using time series data of precipitation and streamflow was carried out next. The analysis included use of storm events with different temporal...
Show moreThis thesis focuses on evaluation of joint occurrence of extreme precipitation and streamflow events at several hydrologic structures in South Florida. An analysis of twelve years storm events and their corresponding peak streamflow events during wet and dry season including annual peaks considering two seasons was performed first. Dependence analysis using time series data of precipitation and streamflow was carried out next. The analysis included use of storm events with different temporal lags from the time of occurrence of peak streamflow events. Bi-variate joint probability was found to be appropriate to analyze the joint occurrence of events. Evaluation of joint exceedence probabilities under two phases of Atlantic multidecadal oscillation (AMO) influencing south Florida was also evaluated. All methodologies are evaluated for application using observations at several structures in the case study region to provide advances and valuable insights on joint extremes of precipitation and streamflows.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3360954
- Subject Headings
- Climatic changes, Precipitation (Meterology), Streamflow, Environmental aspects
- Format
- Document (PDF)
- Title
- Mangrove Morphological Change Across an Environmental Gradients: Implications for Competitive Ability in a Changing Climate.
- Creator
- Standish, Hilary, Proffitt, C. Edward, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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In Florida, mangroves have responded to climate change by slowly migrating northward into traditional salt marsh habitat. However, little is understood about the relationships among mangrove growth form plasticity and environmental conditions. In addition, the effects of the mangrove northward expansion on pre-existing salt marsh communities are unknown, especially any influences of differences in tree morphology. The size, canopy structure, and root structure of the three mangrove species...
Show moreIn Florida, mangroves have responded to climate change by slowly migrating northward into traditional salt marsh habitat. However, little is understood about the relationships among mangrove growth form plasticity and environmental conditions. In addition, the effects of the mangrove northward expansion on pre-existing salt marsh communities are unknown, especially any influences of differences in tree morphology. The size, canopy structure, and root structure of the three mangrove species Rhizophora mangle, Avicennia germinans, and Laguncularia racemosa were measured at six sites along the east coast of Florida. Structural equation modeling was used to evaluate the multivariate relationships between environmental and biotic variables. Mangrove growth form varied widely with environmental variables. The results of this study suggest that R. mangle expansion into salt marsh may rely on interactions with salt marsh and shading as well as on climatic variables, which has implications for future mangrove expansion northward in Florida.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004759, http://purl.flvc.org/fau/fd/FA00004759
- Subject Headings
- Mangrove forests--Florida., Mangrove management., Mangrove ecology., Mangrove conservation., Marine ecosystem management--Florida., Coastal zone management--Florida., Forest ecology., Climatic changes--Florida.
- Format
- Document (PDF)
- Title
- Public Perception of Health Risks Related to Climate Change in Broward County, Florida.
- Creator
- Buck, Jeanmarie A. Steckler, Cameron, Mary, Florida Atlantic University, Dorothy F. Schmidt College of Arts and Letters, Department of Anthropology
- Abstract/Description
-
Scholars agree that global climate change is a major threat to the physical environment, affecting all aspects of life on the planet. However, the general public do not feel that climate change is a major risk or threat, especially to humans. It is important to understand the public’s perception and opinions of climate change as it affects and influences the creation and passing of climate change adaptation and mitigation policies. Specifically, little is known about public perceptions in...
Show moreScholars agree that global climate change is a major threat to the physical environment, affecting all aspects of life on the planet. However, the general public do not feel that climate change is a major risk or threat, especially to humans. It is important to understand the public’s perception and opinions of climate change as it affects and influences the creation and passing of climate change adaptation and mitigation policies. Specifically, little is known about public perceptions in regards to the greater health risk imposed by global climate change. This study examines the public's perception of health risks related to climate change in Broward County, Florida by using mixed methods. An online survey was conducted along with in-person interviews with the general public and a physician. The study found majority of respondents to believe climate change affects health, but lacked an understanding of how it is harmful to their health. It also found that gender affects their perceptions and political ideology appears to have an effect, but the effect of socioeconomic status on their perceptions were unable to be determined at this time. Broward is just developing policies to adapt and mitigate the health effects of climate change.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00004813, http://purl.flvc.org/fau/fd/FA00004813
- Subject Headings
- Environmental health--Florida--Broward County., Health risk assessment--Florida--Broward County., Human beings--Effect of climate on., Climatic changes--Health aspects., Social change--Health aspects., Global warming--Health aspects., Public health surveillance--Florida--Broward County.
- Format
- Document (PDF)
- Title
- Perceived risk versus actual risk to sea-level rise: a case study in Broward County, Florida.
- Creator
- Bolter, Keren P., Hindle, Tobin, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
- Abstract/Description
-
Global climate change stressors downscale to specific local vulnerabilities, requiring customized adaptation strategies. Southeast Florida has a high likelihood of sealevel rise impact to due to the low-lying porous limestone geology. High risk is coupled with high exposure due to high-valued coastal properties, productive ecosystems, and dense populations. Coastal populations are particularly at risk due to erosion, inundation and storm surge, but interior populations are also susceptible to...
Show moreGlobal climate change stressors downscale to specific local vulnerabilities, requiring customized adaptation strategies. Southeast Florida has a high likelihood of sealevel rise impact to due to the low-lying porous limestone geology. High risk is coupled with high exposure due to high-valued coastal properties, productive ecosystems, and dense populations. Coastal populations are particularly at risk due to erosion, inundation and storm surge, but interior populations are also susceptible to rising water tables and extended periods of inundation. All of these impacts are amplified by sea-level rise. Robust sea-level rise adaptation options require significant economic costs. If perceived risk does not adequately line up with actual risk, lack of funds and preparation will prevent implementation of the most effective strategies.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004268, http://purl.flvc.org/fau/fd/FA00004268
- Subject Headings
- Climatic changes -- Florida -- Broward County -- Case studies, Coastal ecology -- Florida -- Broward County -- Case studies, Coastal zone management -- Florida -- Broward County -- Case studies, Hazardous geographic environments -- Florida -- Broward County -- Case studies, Sea level -- Florida -- Broward County -- Case studies
- Format
- Document (PDF)
