Shiromani Jayawardena

• PhD , MSc in Meteorology
• Advisor, SAHF Climate and Weather service at Independent Researcher

The Indian Ocean Dipole (IOD) is a significant driver of ocean-atmosphere coupled phenomena over the equatorial Indian Ocean (IO), and it strongly influences the inter-annual rainfall variability of Sri Lanka. Notably, the relationship between IOD and Sri Lanka rainfall has undergone notable fluctuations over the past decades. This study analyzes t...

The Indian Ocean Dipole (IOD) represents a significant driver of ocean-atmosphere coupled phenomena over the equatorial Indian Ocean (IO), exerting a strong influence on the inter-annual rainfall variability of Sri Lanka. However, the nature of the relationship between the IOD and Sri Lanka rainfall has undergone secular fluctuations over the past...

This paper presents a comprehensive seasonal analysis of disaster incidents with their associated weather systems reported in Sri Lanka from 1907 to 2019. Disaster incidents and weather records were collected from different reliable sources and analysed with the observed weather systems to understand the formation and development of those weather s...

Climate is one of the important factors that influence crop production. Paddy (Oryza sativa L.) is highly impacted by the variations in rainfall that occur within a growing season. This study was mainly focused on the major paddy-growing season in Sri Lanka, Maha season (October to February), under different phases of the Indian Ocean Dipole (IOD)...

Plain Language Summary Extreme rainfall events affect Sri Lanka every year, causing floods, landslides and tremendous losses. Thus, it is important to identify weather patterns that are associated with these events. Furthermore, it is important to understand how the dominant modes of the tropical intraseasonal variability, such as the Madden‐Julian...

Climate change-related changes in temperature and precipitation trends must be investigated at local, regional and global levels. Temperature and precipitation trends in two selected regions having tropical wet and tropical montane climates (i.e., Colombo and Nuwara Eliya respectively) in Sri Lanka were studied for a 30 year period from 1989 to 201...

Sri Lanka is affected by extreme precipitation events every year, which cause floods, landslides and tremendous economic losses. In this study, we use the ERA5 reanalysis dataset to understand their association with 30 weather patterns, which were originally derived to represent the variability of the Indian climate during January–December 1979–201...

The climate outlook for the 2019 southwest monsoon (SWM) season was prepared through an expert assessment of the prevailing global climate conditions and forecasts from different climate models from around the world during the fourteenth session of the South Asian Climate Outlook Forum (SASCOF14). Above-normal rainfall was predicted over Sri Lanka...

The Intergovernmental Panel on Climate Change needs to do more to include the expertise and voices of women, even as numbers and policies improve. The Intergovernmental Panel on Climate Change needs to do more to include the expertise and voices of women, even as numbers and policies improve.

The aim of this study was to assess the application of gridded precipitation datasets for applications in Sri Lanka and to identify suitable products that can be used for hydrological applications in data sparse regions. Here, nine global datasets were considered for this study, and after initial screening, four datasets, such as Integrated Multi‐S...

The influence of the Madden Julian Oscillation (MJO) on rainfall in Sri Lanka (SL) is examined based on 30 years of daily station data from 1981-2010. Composites are constructed for each of the eight phases of the MJO defined with the Real-time Multivariate MJO (RMM) index, using daily rainfall data from 44 stations over SL for four climatic season...

The book provides the outcome of a collaborative work FAO, the Department of Agriculture of Sri Lanka, the Department of Meteorology of Sri Lanka, the University of Peradeniya in Sri Lanka, the University of Cantabria in Spain and the University of Milan in Italy. Future climate change impacts on these crops were evaluated using the Modelling Sys...

The influence of the Madden Julian Oscillation (MJO) on rainfall in Sri Lanka (SL) is examined based on 30 years of daily station data from 1981-2010. Composites are constructed for each of the eight phases of the MJO defined with the Real-time Multivariate MJO (RMM) index, using daily rainfall data from 44 stations over SL for four climatic season...

Ocean-atmospheric teleconnections such as El Niño Southern Oscillation (ENSO) are important climatic determinants in studying inter-and intra-seasonal variability of rainfall. The ENSO takes place in the central eastern equatorial Pacific Ocean. Warm and cold phases of ENSO cycle are termed as El Niño and La Niña, respectively. As it influences the...

Trends in 20 extreme indices of temperature and precipitation are examined for Sri Lanka using high-quality datasets for 19 meteorological stations, for a period between 1980 and 2015. It is evident that annually averaged mean minimum temperatures are increasing across most of Sri Lanka. The differ- ence between maximum and minimum temperatures, di...

This study revealed the influence of Madden Julian oscillation (MJO) and cold surge (CS) on the extreme rainfall events that occurred in Sri Lanka from 19th to 28th December 2014. During this period, the Northeast Monsoon winds over the Bay of Bengal were strengthened by a CS, which intensified convective activity over the Bay of Bengal. Simultaneo...

The anomalous circulation patterns during an unusually prolonged stormy-weather period in Hawaii from 19 February to 2 April 2006 are analyzed and are compared with those of two previously known prolonged heavy-rainfall periods (March 1951 and February 1979). The circulation patterns for these three periods are characterized by 1) a negative Pacifi...

A four-day educational cruise navigated around the leeward side of Oahu and Kauai to observe the thermodynamic and dynamic features of the trade-wind wakes of these small islands by using weather balloons and other onboard atmospheric and oceanographic sensors. This cruise was proposed, designed, and implemented completely by graduate students from...