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City University of New York - City College

Data Fusion and Synergy of Active and Passive Remote Sensing; An application for Freeze Thaw Detections

Abstract

dc:description.abstract

<p>There has been a recent evolvement in the field of remote sensing after increase of number satellites and sensors data which could be fused to produce new data and products. These efforts are mainly focused on using of simultaneous observations from different platforms with different spatial and temporal resolutions. The research dissertation aims to enhance the synergy use of active and passive microwave observations and examine the results in detection land freeze and thaw (FT) predictions. Freeze thaw cycles particularly in high-latitude regions have a crucial role in many applications such as agriculture, biogeochemical transitions, hydrology and ecosystem studies. The dielectric change between frozen ice and melted water can dramatically affect the brightness temperature (TB) signal when water transits from the liquid to the solid phase which makes satellite-based microwave remote sensing unique for characterizing the surface freeze thaw status. Passive microwave (PMW) sensors with coarse resolution (about 25 km) but more frequent observations (at least twice a day and more frequent in polar regions) have been successfully utilized to define surface state in terms of freeze and thaw in the past. Alternatively, active microwave (AMW) sensors provide much higher spatial resolution (about 100 m or less) though with less temporal resolution (each 12 days). Therefore, an integration of microwave data coming from different sensors may provide a more complete estimation of land freeze thaw state. In this regard, the overarching goal of this research is to explore estimating high spatiotemporal freeze and thaw states using the combination of passive and active microwave observations. To obtain a high temporal resolution TB, this study primarily builds an improved diurnal variation of land surface temperature from integration of infrared sensors. In the next step, a half an hourly diurnal cycle of TB based on fusion of different passive sensors is estimated. It should be mentioned that each instrument has its own footprint, resolution, viewing angle, as well as frequency and consequently their data need to be harmonized in order to be combined. Later, data from an AMW sensor with fine spatial resolution are merged and compared to the corresponding passive data in order to find a relation between TB and backscatter data. Subsequently, PMW TB map can be downscaled to a higher spatial resolution or AMW backscatter timeseries can be generalized to high temporal resolution. Eventually, the final high spatiotemporal resolution TB product is used to examine the freeze thaw state for case studies areas in Northern latitudes.</p>

Degree

thesis:*
Name thesis:degree_name
Doctor of Philosophy (Ph.D.)
Level thesis:degree_level
Dissertation
Discipline thesis:degree_discipline
Civil Engineering
Year dc:date.available
2022

Author and committee

dc:creator, dc:contributor.*
Author dc:creator
  • Sharifnezhadazizi, Zahra
Contributors dc:contributor
  • Reza Khanbilvardi
  • Hamidreza Norouzi

Subjects

dc:subject × 16

Identifiers

dc:identifier.*
Repository record dc:identifier
https://academicworks.cuny.edu/cc_etds_theses/1046
OAI identifier oai:identifier
oai:academicworks.cuny.edu:cc_etds_theses-2047

Chain of custody

source
Harvested from
City University of New York - City College
Base URL
academicworks.cuny.edu/do/oai/
Last updated
2026-07-24
Source record
OAI-PMH GetRecord
citation

Sharifnezhadazizi, Zahra. Data Fusion and Synergy of Active and Passive Remote Sensing; An application for Freeze Thaw Detections. Dissertation thesis, 2022. https://academicworks.cuny.edu/cc_etds_theses/1046