Empirical sea ice thickness retrieval during the freeze-up period     from SMOS high incident angle observations

Huntemann, Marcus; Heygster, Georg; Kaleschke, Lars; Krumpen, Thomas; Mäkynen, M.; Drusch, Matthias

doi:10.5194/tc-8-439-2014

Cited by 110 publications

(136 citation statements)

References 27 publications

Supporting

Mentioning

133

Contrasting

Unclassified

Order By: Relevance

“…Notice that T B estimates start at an ice thickness of 5 cm because there is a discontinuity in the Burke model as the thickness of ice tends to zero (e.g. Kaleschke et al, 2010;Mills and Heygster, 2011a;Maaß, 2013;Kaleschke et al, 2013). Compared with T B , the total variation of both AD and PD with ice thickness is significantly smaller, and they are therefore better suited to estimate sea ice concentration.…”

Section: Calibration Of Sea Ice Concentration Using Tie Pointsmentioning

confidence: 99%

“…Martin-Neira et al, 2002;Mecklenburg et al, 2009), SMOS is also making serious inroads in the cryospheric sciences (e.g. Kaleschke et al, 2010Kaleschke et al, , 2012Huntemann et al, 2014). Developed by the European Space Agency (ESA), the SMOS's single payload, called Microwave Imaging Radiometer using Aperture Synthesis (MI-RAS), is an L-band (1.4 GHz, or 21 cm wavelength) passive interferometric radiometer that measures the electromagnetic radiation emitted by Earth's surface.…”

Section: Introductionmentioning

confidence: 99%

“…Mills and Heygster, 2011a;Kaleschke et al, 2013) have recently explored the feasibility of SIC determination using an aircraft-mounted L-band radiometer, a method that extends satellite-based SIC retrievals down to L-band (i.e. SMOS) frequencies has been missing.…”

Section: Introductionmentioning

confidence: 99%

“…As a consequence, the brightness temperature measured by an L-band antenna is emitted not only by the topmost ice surface layer but also by a larger range of deeper layers within the ice. Thanks to that increased penetration in sea ice (about 60 cm depending on ice conditions), the SMOS L-band radiometer is also sensitive to ice thickness (Kaleschke et al, 2012;Huntemann et al, 2014).…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

New methodology to estimate Arctic sea ice concentration from SMOS combining brightness temperature differences in a maximum-likelihood estimator

et al. 2017

View full text Add to dashboard Cite

Abstract. Monitoring sea ice concentration is required for operational and climate studies in the Arctic Sea. Technologies used so far for estimating sea ice concentration have some limitations, for instance the impact of the atmosphere, the physical temperature of ice, and the presence of snow and melting. In the last years, L-band radiometry has been successfully used to study some properties of sea ice, remarkably sea ice thickness. However, the potential of satellite Lband observations for obtaining sea ice concentration had not yet been explored.In this paper, we present preliminary evidence showing that data from the Soil Moisture Ocean Salinity (SMOS) mission can be used to estimate sea ice concentration. Our method, based on a maximum-likelihood estimator (MLE), exploits the marked difference in the radiative properties of sea ice and seawater. In addition, the brightness temperatures of 100 % sea ice and 100 % seawater, as well as their combined values (polarization and angular difference), have been shown to be very stable during winter and spring, so they are robust to variations in physical temperature and other geophysical parameters. Therefore, we can use just two sets of tie points, one for summer and another for winter, for calculating sea ice concentration, leading to a more robust estimate.After analysing the full year 2014 in the entire Arctic, we have found that the sea ice concentration obtained with our method is well determined as compared to the Ocean and Sea Ice Satellite Application Facility (OSI SAF) dataset. However, when thin sea ice is present (ice thickness 0.6 m), the method underestimates the actual sea ice concentration.Our results open the way for a systematic exploitation of SMOS data for monitoring sea ice concentration, at least for specific seasons. Additionally, SMOS data can be synergistically combined with data from other sensors to monitor panArctic sea ice conditions.

show abstract

Section: Calibration Of Sea Ice Concentration Using Tie Pointsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

New methodology to estimate Arctic sea ice concentration from SMOS combining brightness temperature differences in a maximum-likelihood estimator

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Satellite remote sensing, on the other hand, is useful to monitor ice thickness variations regularly over much larger areas. On a still experimental basis, data of L-band passive microwave sensors, such as for example the Soil Moisture and Ocean Salinity mission (SMOS) radiometer, have been employed to retrieve thickness of sea ice thinner than about 0.5 m. The limitation of this approach is that it is only possible for very high (almost 100 %) sea ice concentration and in cold freezing conditions (Tian-Kunze et al, 2014;Huntemann et al, 2014). A space-borne altimeter has been used primarily to map ice thickness, and to monitor and study trends in thickness changes.…”

Section: Introductionmentioning

confidence: 99%

Retrieval of the thickness of undeformed sea ice from simulated C-band compact polarimetric SAR images

et al. 2016

View full text Add to dashboard Cite

Abstract. In this paper we introduce a parameter for the retrieval of the thickness of undeformed first-year sea ice that is specifically adapted to compact polarimetric (CP) synthetic aperture radar (SAR) images. The parameter is denoted as the "CP ratio". In model simulations we investigated the sensitivity of the CP ratio to the dielectric constant, ice thickness, ice surface roughness, and radar incidence angle. From the results of the simulations we deduced optimal sea ice conditions and radar incidence angles for the ice thickness retrieval. C-band SAR data acquired over the Labrador Sea in circular transmit and linear receive (CTLR) mode were generated from RADARSAT-2 quad-polarization images. In comparison with results from helicopter-borne measurements, we tested different empirical equations for the retrieval of ice thickness. An exponential fit between the CP ratio and ice thickness provides the most reliable results. Based on a validation using other compact polarimetric SAR images from the same region, we found a root mean square (rms) error of 8 cm and a maximum correlation coefficient of 0.94 for the retrieval procedure when applying it to level ice between 0.1 and 0.8 m thick.

show abstract

Arctic sea ice in transformation: A review of recent observed changes and impacts on biology and human activity

et al. 2014

View full text Add to dashboard Cite

Sea ice in the Arctic is one of the most rapidly changing components of the global climate system. Over the past few decades, summer areal extent has declined over 30%, and all months show statistically significant declining trends. New satellite missions and techniques have greatly expanded information on sea ice thickness, but many uncertainties remain in the satellite data and long-term records are sparse. However, thickness observations and other satellite-derived data indicate a 40% decline in thickness, due in large part to the loss of thicker, older ice cover. The changes in sea ice are happening faster than models have projected. With continued increasing temperatures, summer ice-free conditions are likely sometime in the coming decades, though there are substantial uncertainties in the exact timing and high interannual variability will remain as sea ice decreases. The changes in Arctic sea ice are already having an impact on flora and fauna in the Arctic. Some species will face increasing challenges in the future, while new habitat will open up for other species. The changes are also affecting people living and working in the Arctic. Native communities are facing challenges to their traditional ways of life, while new opportunities open for shipping, fishing, and natural resource extraction. Significant progress has been made in recent years in understanding of Arctic sea ice and its role in climate, the ecosystem, and human activities. However, significant challenges remain in furthering the knowledge of the processes, impacts, and future evolution of the system.

show abstract

Empirical sea ice thickness retrieval during the freeze-up period from SMOS high incident angle observations

Cited by 110 publications

References 27 publications

New methodology to estimate Arctic sea ice concentration from SMOS combining brightness temperature differences in a maximum-likelihood estimator

New methodology to estimate Arctic sea ice concentration from SMOS combining brightness temperature differences in a maximum-likelihood estimator

Retrieval of the thickness of undeformed sea ice from simulated C-band compact polarimetric SAR images

Arctic sea ice in transformation: A review of recent observed changes and impacts on biology and human activity

Contact Info

Product

Resources

About