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My research finds its form in providing answers to questions related to coasts and ocean, based on my knowledge of physical oceanography and experience in data sciences.
Dr. Zafer Defne received his PhD in Coastal and Ocean Engineering from Georgia Institute of Technology, with a minor in Information Technology Applications in Oceanography. His expertise includes computational fluid dynamics and data analysis. His work on numerical modeling of coastal ocean has been used to assess storm surge, residual circulation, sediment transport and water quality, as well as marine renewable energy. His recent research is on assessment of the physical state of coastal wetlands using geospatial data.
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The USGS is assessing the physical condition of coastal wetlands and their response to external forces, using field observations and remote-sensing data. The U.S.
The USGS is assessing the physical condition of coastal wetlands and their response to external forces, using field observations and remote-sensing data. The U.S.
The collection provides a motivation for the USGS coastal wetland research and individual web apps where users can browse each CONUS-wide data separately (relative tidal elevation, unvegetated-vegetated ratio, and aboveground biomass). It also provides a Collection viewer, where users can browse the CONUS-wide collection on the same map.
The collection provides a motivation for the USGS coastal wetland research and individual web apps where users can browse each CONUS-wide data separately (relative tidal elevation, unvegetated-vegetated ratio, and aboveground biomass). It also provides a Collection viewer, where users can browse the CONUS-wide collection on the same map.
Users can navigate the collection by clicking on the tiles on the cover page or the tabbed menu. With the Collection viewer, users can use a swipe tool to compare layers and click to see the values for each pixel. Users can also add other data to the viewer and bookmark any locations of interest.
Users can navigate the collection by clicking on the tiles on the cover page or the tabbed menu. With the Collection viewer, users can use a swipe tool to compare layers and click to see the values for each pixel. Users can also add other data to the viewer and bookmark any locations of interest.
Pre- and post-Hurricane Dorian aerial imagery showing extreme sediment transport, overwash and breaches along the barrier islands of the North Carolina coast.
Pre- and post-Hurricane Dorian aerial imagery showing extreme sediment transport, overwash and breaches along the barrier islands of the North Carolina coast.
Example from development of an atmospheric model for Hurricane Florence. The images display a comparison between the control case, WRF-ROMS-SWAN modeling system and the multi-sensor (radar and rain) precipitation observations during the calibration of the model.
Example from development of an atmospheric model for Hurricane Florence. The images display a comparison between the control case, WRF-ROMS-SWAN modeling system and the multi-sensor (radar and rain) precipitation observations during the calibration of the model.
Example from development of an atmospheric model for Hurricane Florence. The animation shows the changing atmospheric pressure and wind fields during the storm as simulated by the model. Arrows display wind direction, colors indicate atmospheric pressure ranging from 97,500 pascals (red) to 102,460 pascals (blue).
Example from development of an atmospheric model for Hurricane Florence. The animation shows the changing atmospheric pressure and wind fields during the storm as simulated by the model. Arrows display wind direction, colors indicate atmospheric pressure ranging from 97,500 pascals (red) to 102,460 pascals (blue).
Hurricane Florence numerical modeling: Cape Fear River basin boundaries, topography, river streams and measurement locations. USGS streamflow and rain gages, and Community Collaborative Rain, Hail and Snow Network (CoCoRaHS) gages are shown. Stream order increases going from branches to the main channel indicating merging surface water flow.
Hurricane Florence numerical modeling: Cape Fear River basin boundaries, topography, river streams and measurement locations. USGS streamflow and rain gages, and Community Collaborative Rain, Hail and Snow Network (CoCoRaHS) gages are shown. Stream order increases going from branches to the main channel indicating merging surface water flow.
Hurricane Florence numerical modeling: The Weather Research and Forecasting Model Hydrological modeling system (WRF-Hydro) is used to simulate surface and subsurface flows on land.
Hurricane Florence numerical modeling: The Weather Research and Forecasting Model Hydrological modeling system (WRF-Hydro) is used to simulate surface and subsurface flows on land.
Hurricane Sandy (2012) modeling: Modeling can reveal the contributions from underlying processes individually. These images show contribution from offshore surge (change in water level) and offshore waves to maximum water levels (in meters) within a bay during a coastal storm.
Hurricane Sandy (2012) modeling: Modeling can reveal the contributions from underlying processes individually. These images show contribution from offshore surge (change in water level) and offshore waves to maximum water levels (in meters) within a bay during a coastal storm.
Photo of a boardwalk over a saltmarsh creek showing people.
Photo of a boardwalk over a saltmarsh creek showing people.
Photo showing floating cages for oyster farming in a marsh creek exposed at low tide.
Photo showing floating cages for oyster farming in a marsh creek exposed at low tide.
Photo showing different species of salt tolerant plants near a saltmarsh.
Photo showing different species of salt tolerant plants near a saltmarsh.
Photo of a saltmarsh platform showing vegetation on on top of the banks of a tidal creek. It shows the general setting of a saltmarshes that experience wet and dry periods with the tides within a day.
Photo of a saltmarsh platform showing vegetation on on top of the banks of a tidal creek. It shows the general setting of a saltmarshes that experience wet and dry periods with the tides within a day.
Hurricane Florence (2018) modeling: The coupled model captures the stages of compound flooding in the Cape Fear River Estuary starting with swell from offshore, followed by storm surge from the ocean side, later transitioning to flooding from land side with the storm water runoff because of rain.
Hurricane Florence (2018) modeling: The coupled model captures the stages of compound flooding in the Cape Fear River Estuary starting with swell from offshore, followed by storm surge from the ocean side, later transitioning to flooding from land side with the storm water runoff because of rain.
Edwin B. Forsythe National Wildlife Refuge, New Jersey Study SIte
Edwin B. Forsythe National Wildlife Refuge, New Jersey Study SIte
Browse graphic of Edwin B Forsythe National Wildlife Refuge study area
Browse graphic of Edwin B Forsythe National Wildlife Refuge study area
The USGS is assessing the physical condition of coastal wetlands and their response to external forces, using field observations and remote-sensing data. The U.S.
The USGS is assessing the physical condition of coastal wetlands and their response to external forces, using field observations and remote-sensing data. The U.S.
The collection provides a motivation for the USGS coastal wetland research and individual web apps where users can browse each CONUS-wide data separately (relative tidal elevation, unvegetated-vegetated ratio, and aboveground biomass). It also provides a Collection viewer, where users can browse the CONUS-wide collection on the same map.
The collection provides a motivation for the USGS coastal wetland research and individual web apps where users can browse each CONUS-wide data separately (relative tidal elevation, unvegetated-vegetated ratio, and aboveground biomass). It also provides a Collection viewer, where users can browse the CONUS-wide collection on the same map.
Users can navigate the collection by clicking on the tiles on the cover page or the tabbed menu. With the Collection viewer, users can use a swipe tool to compare layers and click to see the values for each pixel. Users can also add other data to the viewer and bookmark any locations of interest.
Users can navigate the collection by clicking on the tiles on the cover page or the tabbed menu. With the Collection viewer, users can use a swipe tool to compare layers and click to see the values for each pixel. Users can also add other data to the viewer and bookmark any locations of interest.
Pre- and post-Hurricane Dorian aerial imagery showing extreme sediment transport, overwash and breaches along the barrier islands of the North Carolina coast.
Pre- and post-Hurricane Dorian aerial imagery showing extreme sediment transport, overwash and breaches along the barrier islands of the North Carolina coast.
Example from development of an atmospheric model for Hurricane Florence. The images display a comparison between the control case, WRF-ROMS-SWAN modeling system and the multi-sensor (radar and rain) precipitation observations during the calibration of the model.
Example from development of an atmospheric model for Hurricane Florence. The images display a comparison between the control case, WRF-ROMS-SWAN modeling system and the multi-sensor (radar and rain) precipitation observations during the calibration of the model.
Example from development of an atmospheric model for Hurricane Florence. The animation shows the changing atmospheric pressure and wind fields during the storm as simulated by the model. Arrows display wind direction, colors indicate atmospheric pressure ranging from 97,500 pascals (red) to 102,460 pascals (blue).
Example from development of an atmospheric model for Hurricane Florence. The animation shows the changing atmospheric pressure and wind fields during the storm as simulated by the model. Arrows display wind direction, colors indicate atmospheric pressure ranging from 97,500 pascals (red) to 102,460 pascals (blue).
Hurricane Florence numerical modeling: Cape Fear River basin boundaries, topography, river streams and measurement locations. USGS streamflow and rain gages, and Community Collaborative Rain, Hail and Snow Network (CoCoRaHS) gages are shown. Stream order increases going from branches to the main channel indicating merging surface water flow.
Hurricane Florence numerical modeling: Cape Fear River basin boundaries, topography, river streams and measurement locations. USGS streamflow and rain gages, and Community Collaborative Rain, Hail and Snow Network (CoCoRaHS) gages are shown. Stream order increases going from branches to the main channel indicating merging surface water flow.
Hurricane Florence numerical modeling: The Weather Research and Forecasting Model Hydrological modeling system (WRF-Hydro) is used to simulate surface and subsurface flows on land.
Hurricane Florence numerical modeling: The Weather Research and Forecasting Model Hydrological modeling system (WRF-Hydro) is used to simulate surface and subsurface flows on land.
Hurricane Sandy (2012) modeling: Modeling can reveal the contributions from underlying processes individually. These images show contribution from offshore surge (change in water level) and offshore waves to maximum water levels (in meters) within a bay during a coastal storm.
Hurricane Sandy (2012) modeling: Modeling can reveal the contributions from underlying processes individually. These images show contribution from offshore surge (change in water level) and offshore waves to maximum water levels (in meters) within a bay during a coastal storm.
Photo of a boardwalk over a saltmarsh creek showing people.
Photo of a boardwalk over a saltmarsh creek showing people.
Photo showing floating cages for oyster farming in a marsh creek exposed at low tide.
Photo showing floating cages for oyster farming in a marsh creek exposed at low tide.
Photo showing different species of salt tolerant plants near a saltmarsh.
Photo showing different species of salt tolerant plants near a saltmarsh.
Photo of a saltmarsh platform showing vegetation on on top of the banks of a tidal creek. It shows the general setting of a saltmarshes that experience wet and dry periods with the tides within a day.
Photo of a saltmarsh platform showing vegetation on on top of the banks of a tidal creek. It shows the general setting of a saltmarshes that experience wet and dry periods with the tides within a day.
Hurricane Florence (2018) modeling: The coupled model captures the stages of compound flooding in the Cape Fear River Estuary starting with swell from offshore, followed by storm surge from the ocean side, later transitioning to flooding from land side with the storm water runoff because of rain.
Hurricane Florence (2018) modeling: The coupled model captures the stages of compound flooding in the Cape Fear River Estuary starting with swell from offshore, followed by storm surge from the ocean side, later transitioning to flooding from land side with the storm water runoff because of rain.
Edwin B. Forsythe National Wildlife Refuge, New Jersey Study SIte
Edwin B. Forsythe National Wildlife Refuge, New Jersey Study SIte
Browse graphic of Edwin B Forsythe National Wildlife Refuge study area
Browse graphic of Edwin B Forsythe National Wildlife Refuge study area