Qualification: 
Ph.D
sajithv@am.amrita.edu

Sajith Vezhapparambu currently serves as a Research Associate at the Amrita Center for Wireless Networks & Applications (Amrita WNA), Amritapuri.

Experience Summary

  • Land surface-climate interactions (Tropical, Multitude and Arctic)
  • Land Surface-Atmosphere coupled modeling
  • Data Parsing and analysis of big data sets (Satellite data and climate model outputs) with Python, GDAL, ArcGIS, GrADS

Research Experience

2017 October - present Working as a Research Associate (Amrita Center for Wireless Networks and Applications, Amrita Viswa Vidyapeetham, Amrithapuri, Kerala, India) on a project named “Characterizing and modelling the impact of soil moisture heterogeneity on convective processes over the Indian subcontinent” funded by SERB, DST, Government of India.
Decadal Changes in soil moisture over the Indian sub-continent and its relationship with precipitation, using the soil moisture product from European Space Agency’s Climate Change Initiative (ESA-CCI), combining passive and active microwave derived data
2014 December –2016 December Worked as a Researcher in the project “Approaches for integrated assessment of forest ecosystem services under large scale bioenergy utilization (Ecoservice; Norwegian Research Council, 2014 – )”, Industrial Ecology, NTNU, Norway.
Main contribution: In Data parsing and harmonizing 12 years of data comprising MODIS albedo, climate parameters and LULC/forest inventory.
From 2012 May -2014 May Worked as a Post-Doctoral Research Associate, Natural Resources and the Environment, CSIR, South Africa.
Project title: Leveraging regional climate models to address land-atmosphere feedbacks. Validating and parameterizing CABLE (land surface model) using flux tower data.
From 2011-2012 Post-doctoral research associate
NASA ROSESNNH09ZDA001-IDS, “Interaction and feedbacks between biomass burning and water-cycle dynamics across the northern sub-Saharan African region”
From 2004-2011 PhD candidate at Department of Geosciences, University of Missouri-Kansas City (UMKC)
Teaching assistant, department of geosciences, UMKC; UMKC Dissertation Research Fellow; UMKC Chancellor's Doctoral Fellow, Kansas city, USA.
From 2000-2004 Senior Research fellow (CUSAT, Kerala, India)
Worked on a Dissertation research, “Studies on the variations of moisture over North Indian Ocean during summer monsoon using TRMM Microwave Imager”.
From 1997-1999 Junior research Fellow (CUSAT, Kerala, India)
The environmental impact assessment project “Carrying capacity based development planning study for greater Kochi region” funded by Ministry of environment and forest, India. My duties included: Map making, air-pollution and high frequency meteorological data collection and analysis

Teaching Experience

From 2005:2012 Guest lecturer and laboratory instructor (Department of Geosciences, UMKC, USA)
At UMKC, I served as a guest lecturer for 2011-2012and a teaching assistant for the period of 2005-2010 for the following courses: (1) Introduction to weather and Climate; (2) Understanding the Earth- lab; (3) Introduction to GIS. (Arc View); and (4) Satellite Climatology. My responsibilities in those courses were: lecturing, participating in course and laboratory material development and running laboratory sessions.

Education

YEAR DEGREE/PROGRAM INSTITUTION
May 2011 Inter-disciplinary Ph.D. (Geosciences and Physics) University of Missouri- Kansas City, USA (UMKC) with a 3.914 GPA .
1995 January - 1997 January M.Sc Meteorology Cochin University of Science and Technology, India (CUSAT)
1991 - 1994 B.Sc Mathematics M.G. University, Kerala, India
  Advanced GIS Developer Certificate University of Missouri Kansas City, USA

Honors and Awards

  • UMKC Graduate school Dissertation research Fellowship for one year 2009-2010
  • UMKC Chancellor's Doctoral Fellowship for two years 2007-2009

Project Reports

  • Sajith Vezhapparambu, Sally Archibald and Francois Engelbrecht, 2013: Towards a stable coupled Land-atmosphere modeling system. CSIR/NRE/GC/IR/2013/0053/B.

Presentations & Posters

  • Francesco Cherubini, Xiangping Hu, Sajith Vezhapparambu, and Anders Stromman, “High-resolution Mapping and Modelling of Surface Albedo in Norwegian Boreal Forests: From Remotely Sensed Data to Predictions”, EGU2017-8051, 2017
  • Archibald S., S. Vezhapparambu, R. J. Scholes, A. Nickless “Coupling the Land and the Atmosphere: Predicting carbon fluxes in Southern” , SA ICON workshop, August, 2012
  • Jimmy O. Adegoke , Sajith Vezhapparambu, Christopher L. Castro and Kevin P. Gallo “Land surface influence on summer climate predictability in the United States Midwest”: Conference: Climate Prediction Program for the Americas: PI’s Meeting, At Silver Spring, MD, September 2008.  
  • Vezhapparambu, Sajith, Jimmy O. Adegoke, Christopher L. Castro, Roger A. Pielke Sr., Andrew M. Carleton, and Kevin P. Gallo: “The Impact of Soil Moisture and Surface Vegetation Variability on the Organization of Summer Convective Activity in the US Midwest: August 2000 Case Study”, NSF work shop (Detecting the Atmospheric Response to the Changing Face of the Earth: A Focus on Human-Caused Regional Climate Forcings, Land-Cover/Land-Use Change, and Data Monitoring, August 27-29, 2007 Boulder, CO)
  • Vezhapparambu, Sajith, Jimmy O. Adegoke, Diurnal Variability of Atmospheric Water Vapor Over North Indian Ocean Derived from TRMM/TMI and its Influence on Monsoon Variability, ( at the 2005 annual meeting of AAG, Denver, Colorado)

Publications

Publication Type: Journal Article

Year of Publication Publication Type Title

2018

Journal Article

A. Arvesen, Cherubini, F., Serrano, Gdel Alamo, Astrup, R., Becidan, M., Belbo, H., Goile, F., Grytli, T., Guest, G., Lausselet, C., Rørstad, P. Kristian, Rydså, M. Seljeskog, Skreiberg, Ø., Sajith Vezhapparambu, and Strømman, A. Hammer, “Cooling Aerosols and Changes in Albedo Counteract Warming from CO2 and Black Carbon from Forest Bioenergy in Norway”, Scientific Reports, vol. 8, 2018.[Abstract]


Climate impacts of forest bioenergy result from a multitude of warming and cooling effects and vary by location and technology. While past bioenergy studies have analysed a limited number of climate-altering pollutants and activities, no studies have jointly addressed supply chain greenhouse gas emissions, biogenic CO2 fluxes, aerosols and albedo changes at high spatial and process detail. Here, we present a national-level climate impact analysis of stationary bioenergy systems in Norway based on wood-burning stoves and wood biomass-based district heating. We find that cooling aerosols and albedo offset 60–70% of total warming, leaving a net warming of 340 or 69 kg CO2e MWh−1 for stoves or district heating, respectively. Large variations are observed over locations for albedo, and over technology alternatives for aerosols. By demonstrating both notable magnitudes and complexities of different climate warming and cooling effects of forest bioenergy in Norway, our study emphasizes the need to consider multiple forcing agents in climate impact analysis of forest bioenergy.

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2017

Journal Article

F. Cherubini, Sajith Vezhapparambu, Bogren, W., Astrup, R., and Strømman, A. Hammer, “Spatial, Seasonal, and Topographical Patterns of Surface Albedo in Norwegian Forests and Cropland”, International Journal of Remote Sensing, vol. 38, pp. 4565-4586, 2017.[Abstract]


Land surface albedo is a key parameter of the Earth’s climate system. It has high variability in space, time, and land cover and it is among the most important variables in climate models. Extensive large-scale estimates can help model calibration and improvement to reduce uncertainties in quantifying the influence of surface albedo changes on the planetary radiation balance. Here, we use satellite retrievals of Moderate Resolution Imaging Spectroradiometer (MODIS) surface albedo (MCD43A3), high-resolution land-cover maps, and meteorological records to characterize climatological albedo variations in Norway across latitude, seasons, land-cover type (deciduous forests, coniferous forests, and cropland), and topography. We also investigate the net changes in surface albedo and surface air temperature through site pair analysis to mimic the effects of land-use transitions between forests and cropland and among different tree species. We find that surface albedo increases at increasing latitude in the snow season, and cropland and deciduous forests generally have higher albedo values than coniferous forests, but for few days in spring. Topography has a large influence on MODIS albedo retrievals, with values that can change up to 100% for the same land-cover class (e.g. spruce in winter) under varying slopes and aspect of the terrain. Cropland sites have surface air temperature higher than adjacent forested sites, and deciduous forests are slightly colder than adjacent coniferous forests. By integrating satellite measurements and high-resolution vegetation maps, our results provide a large semi-empirical basis that can assist future studies to better predict changes in a fundamental climate-regulating service such as surface albedo.

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2013

Journal Article

A. Amidu, Evison, K., Alabi, S., Sajith Vezhapparambu, and Jimmy, A., “Assessing the Impact of Land Use/land Cover and Climate Changes on Water Stress in the Derived Savanna”, Proceedings of H01, IAHS-IAPSO-IASPEI Assembly, 2013.[Abstract]


Understanding the impact of land use/land cover (LULC) and climate patterns on basin runoff is necessary in assessing basin water stress. This assessment requires long-term observed rainfall time series and LULC spatial data. In order to assess the potential water stress, the study used long-term (1981–2007) rainfall data to drive the Pitman monthly rainfall–runoff model to assess changes in runoff for three selected basins: Asa, Ogun and Owena. In spite of the limitations in the availability of spatio-temporal hydro-meteorological data, the model results revealed commensurate increase in the runoff coefficient with decreases in forest cover between 1981 and 2000. Low runoff coefficients of 5.3%, 12.0% and 6.4% were recorded for Asa, Ogun and Owena basins based on C-CAM projection of low rainfall for 2010–2050. These indicated that in the future, water stress in Asa and Owena basins would be much higher, when compared with Ogun basin

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2009

Journal Article

A. A. Balogun, Adegoke, J. O., Sajith Vezhapparambu, Mauder, M., McFadden, J. P., and Gallo, K., “Surface Energy Balance Measurements Above an Exurban Residential Neighbourhood of Kansas City, Missouri”, Boundary-Layer Meteorology, vol. 133, p. 299, 2009.[Abstract]


Previous measurements of urban energy balances generally have been limited to densely built, central city sites and older suburban locations with mature tree canopies that are higher than the height of the buildings. In contrast, few data are available for the extensive, open vegetated types typical of low-density residential areas that have been newly converted from rural land use. We made direct measurements of surface energy fluxes using the eddy-covariance technique at Greenwood, a recently developed exurban neighbourhood near Kansas City, Missouri, USA, during an intensive field campaign in August 2004. Energy partitioning was dominated by the latent heat flux under both cloudy and near clear-sky conditions. The mean daytime Bowen ratio ($\beta$) values were 0.46, 0.48, and 0.47 respectively for the cloudy, near clear-sky and all-sky conditions. Net radiation (R n ) increased rapidly from dawn (−34 and −58W m−2) during the night to reach a maximum (423 and 630W m−2) after midday for cloudy and near clear-sky conditions respectively. Mean daytime values were 253 and 370W m−2, respectively for the cloudy and near clear-sky conditions, while mean daily values were 114 for cloudy and 171W m−2 for near clear-sky conditions, respectively. Midday surface albedo values were 0.25 and 0.24 for the cloudy and near clear-sky conditions, respectively. The site exhibited an angular dependence on the solar elevation angle, in contrast to previous observations over urban and suburban areas, but similar to vegetated surfaces. The latent heat flux (Q E ), sensible heat flux (Q H ), and the residual heat storage $Δ$Q s terms accounted for between 46–58{%}, 21–23{%}, and 18–31{%} of R n , respectively, for all-sky conditions and time averages. The observed albedo, R n , and Q E values are higher than the values that have been reported for suburban areas with high summer evapotranspiration rates in North America. These results suggest that the rapidly growing residential areas at the exurban fringe of large metropolitan areas have a surface energy balance that is more similar to the rural areas from which they were developed than it is to the older suburbs and city centres that make up the urban fabric to which they are being joined

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2009

Journal Article

R. Mahmood, Pielke, R. A., Sr., K. G. Hubbard, Niyogi, D., Bonan, G., Lawrence, P., Baker, B., McNider, R., ,, Etter, A., Gameda, S., Qian, B., Carleton, A., Beltran-Przekurat, A., Chase, T., Quintanar, A. I., Adegoke, J. O., Sajith Vezhapparambu, Conner, G., Asefi, S., Sertel, E., Legates, D. R., Wu, Y., Hale, R., Frauenfeld, O. W., Watts, A., Shepherd, M., Mitra, C., Anantharaj, V. G., ,, Lund, R., Nordfelt, A., Blanken, P., Du, J., Chang, H. - I., Leeper, R., Nair, U. S., Dobler, S., Deo, R., and Syktus, J., “Impacts of Land Use and Cover Change on Climate and Future Research Priorities”, Bull. Amer. Meteor. Soc, , vol. 91, no. 1, pp. 37-46, 2009.

2008

Journal Article

A. M. Carleton, Travis, D. J., Master, K., and Sajith Vezhapparambu, “Composite Atmospheric Environments of Jet Contrail Outbreaks for the United States”, Journal of Applied Meteorology and Climatology, vol. 47, pp. 641-667, 2008.[Abstract]


Abstract The cirrus-level “condensation trails” (contrails) produced by jet aircraft are considered to influence surface climate and its recent changes. To reveal the synoptic atmospheric environments typically associated with multiple co-occurrences of contrails occurring in otherwise clear or partly cloudy skies (outbreaks) for the United States, and ultimately to assist in forecasting these events, a composite (i.e., multicase average) “synoptic climatology” at regional scales is developed for the midseason months (January, April, July, October) of 2000–02. The NCEP–NCAR reanalysis data that emphasize upper-troposphere (UT) variables are allied with manually identified outbreaks appearing on satellite Advanced Very High Resolution Radiometer digital data, using a geographic information system. The highest frequencies of outbreaks by far occur in the Midwest (32.6% of all-U.S. total), followed by the Northeast (17.6%) and Southeast (17.2%). In these regions, all of which have a high density of jet air traffic, an additional 2% cirrus cloud coverage from outbreak-related contrails is inferred. Large interannual and interseasonal variations in contrail outbreak frequencies support the role of meteorological variations. For most regions, the outbreak-associated synoptic circulation composite conditions involve UT ridging and a higher and colder tropopause than the climatological average; meridionally enhanced gradients of the UT vertical motion, located between sinking air to the east (in the ridge) and rising air to the west, in advance of a trough; similarly strong gradients of mid–upper-troposphere humidity, comprising dry air located to the east and moist air to the west; and horizontal speed shear ahead of an advancing jet stream. Notwithstanding, there is a geography (i.e., areal differentiation) to contrail outbreak environments: composites for the Northeast suggest an influence of land–sea contrasts on synoptic systems and, therefore, on contrail outbreaks. For the Northwest, there is evident a greater impact of horizontal wind shear contrasted with other regions. The synoptic climatology results are supported by the all-U.S. averages of contrail outbreak UT conditions [climate diagnostics (CDNs)] previously determined for early–mid-September periods of 1995–2001. Moreover, a comparison of these CDNs with those derived for nearby thick natural clouds, including cirrus, helps to clarify their different synoptic associations: the UT conditions typical of thick clouds represent an intensification of those associated with contrail outbreaks and include the greater upward vertical motion, moister air, and stronger westerly winds characteristic of a trough. Given the location of most contrail outbreaks downstream of multilayered cloud systems, contrails may help to extend the “natural” cirrus and cirrostratus spatial coverage.

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2006

Journal Article

Sajith Vezhapparambu, O., A. Jimmy, K., R. Santosh, S., R. Mohan H., Vinod, K., and N., P. P., “Evaluation of Daily and Diurnal Signals of Total Precipitable Water (TPW) Over the Indian Ocean based on TMI Retrieved 3-day Composite Estimates and Radiosonde Data”, International Journal of Climatology, vol. 27, pp. 761-770, 2006.[Abstract]


Abstract Tropical rainfall measuring mission (TRMM) TRMM microwave imager (TMI) retrieved total precipitable water (TPW) has been shown in previous studies to be useful for characterizing energy transport and rainfall variability over water bodies. In this study, 3-day composite TPW values during the monsoon months of June–September in 1999 and 2003 were evaluated against radiosonde derived TPW over the coastal regions of Indian Ocean. The radiosonde measurements were from coastal locations, island stations and ship-based observations made during the 1999 Bay of Bengal Monsoon Experiment (BOBMEX). Our study is one of the first attempts to compare TMI-derived TPW with the BOBMEX data. Root mean square (RMS) error of 8.1 mm and a bias of −0.76 mm were obtained for TMI 3-day composite TPW data with respect to the radiosonde data over the Indian coastal regions. TMI overestimated (underestimated) radiosonde measurements under dry (wet) atmospheric conditions. Daily TMI-derived TPW was also validated with radiosonde measurements from the BOBMEX data for the period 21 July–28 August 1999. Diurnal signals of TPW over Bay of Bengal were found to be comparable to the in situ measurements during the same period. Copyright © 2006 Royal Meteorological Society

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2003

Journal Article

Sajith Vezhapparambu, R., S. K., and S., R. Mohan H., “Intraseasonal oscillation of total precipitable water over North Indian Ocean and its application in the diagnostic study of coastal rainfall”, Geophysical Research Letters, vol. 30, 2003.[Abstract]


TRMM Microwave Imager (TMI) is reported to be a useful sensor to measure the atmospheric and oceanic parameters even in cloudy conditions. Vertically integrated specific humidity, Total Precipitable Water (TPW) retrieved from the water vapour absorption channel (22GHz.) along with 10m wind speed and rain rate derived from TMI is used to investigate the moisture variation over North Indian Ocean. Intraseasonal Oscillations (ISO) of TPW during the summer monsoon seasons 1998, 1999, and 2000 over North Indian Ocean is explored using wavelet analysis. The dominant waves in TPW during the monsoon periods and the differences in ISO over Arabian Sea and Bay of Bengal are investigated. The northward propagation of TPW anomaly and its coherence with the coastal rainfall is also studied. For the diagnostic study of heavy rainfall spells over the west coast, the intrusion of TPW over the North Arabian Sea is seen to be a useful tool.

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Faculty Research Interest: