On people's perceptions of climate change and its impacts in a hotspot of global warming

Abstract

The Hindu Kush Himalayan region is a global hotspot for climate change and highly vulnerable to its direct and indirect impacts. Understanding people's perception of climate change is crucial for effective adaptation strategies. We conducted a study by using quantitative (Household survey, n = 660) and qualitative data collection tools (Focus group discussion, n = 12; In-depth interviews, n = 27) in central Nepal encompassing three altitudinal regions: Lowland (<1000 m amsl; Terai region), Midland (1000-1500 m amsl; hilly region) and Highland (1500-2100 m amsl; mountainous region). We analyzed 37 years (1981-2017) of climatic data from respective districts (Lowland: Chitwan, Dhading; Midland: Kathmandu, Lalitpur; Highland: Nuwakot, Rasuwa). People's perception was compared with climate extreme indices measured along these regions and evaluated if they accurately recognized the impacts on the environment and human health. Our findings show significant climate changes, including rising summer temperature, region-specific winter temperatures and extended monsoon seasons in Nepal. Participants in our study accurately perceived these trends but misperceived heavy precipitation patterns. Reported impacts are rise in crop diseases, human diseases, vector expansion and climate induced disasters like floods, landslides, and water resource depletion, with perception accuracy varying by region. These insights highlight the importance of understanding regional and cross-regional perceptions in relation to climate data in order to develop tailored climate adaptation strategies. Policymakers can use this information to establish region-specific educational and communication initiatives, addressing communities' distinctive vulnerabilities and needs across diverse landscapes. Such approaches can enhance equitable and effective climate resilience in subtropical to alpine regions.

Fig 1. Map of the study area, Nepal.

(A) Bagmati Province (in dark grey) where the altitudinal gradient is located. (B) Study districts from Lowland (Chitwan, Dhading) and Midland (Kathmandu, Lalitpur) to Highland (Nuwakot, Rasuwa) between 100 to 2100 m amsl. The study sites are indicated with black dots. The map was created using RStudio 2024.04.02 with R packages ggplot2, sf, dplyr and ggspatial.

Fig 2. People’s perceptions on climate change and variability.

Heat map of the perceptions P1 to P6 (% participants, p-value from Chi-square test) in accordance with the altitudinal residence of the participants in Lowland, Midland and Highland or their general residence in Central Nepal. Detailed responses of participants are given in S8 Fig (details S4 File).

Fig 3. The match between the perceptions P1-P2 and the seasonal precipitation/climate parameters.

Heat map of the perceptions P1 and P2 (given as fractions of the total answers) and the trend (Sen’s slope) over the last 37 years (1981–2017) of the summer/monsoon season and winter-related climate extreme indices (Table 1) in accordance with the altitudinal residence of participants in Lowland, Midland and Highland or their general residence in Central Nepal. Significant climate indicators from the trend analysis (Mann-Kandall test) over the last 37 years (1981–2017) are marked with a asterisk (* p < 0.05, ** p < 0.01, *** p < 0.0001). Significant climate indicators (Mann-Whitney U-test) in the 30 years (1981–2010) vs. 7 years (2011–2017) comparison, after FDR correction, are marked in bold. In the Highlands, no tropical nights (TR) were recorded (details S4 File).

Fig 4. The match between the perceptions P4-P6 and the seasonal precipitation/climate parameters.

Heat map of the perceptions P4 –P6 (given as fractions of the total answers) and the trend (Sen’s slope) over the past 37 years (1981–2017) of seasonal and annual precipitation-related climate extreme indices (Table 1) in accordance with the altitudinal residence of the participants in Lowland, Midland and Highland or their general residence in Central Nepal. Significant indicators from the trend analysis (Mann- Kendall test) over the past 37 years (1981–2017) are marked with an asterisk (* p < 0.05, ** p < 0.01, *** p < 0.0001). Significant climate indicators (Mann-Whitney U-test) in the 30 years (1981–2010) vs. 7 years (2011–2017) comparison, after FDR correction, are marked in bold. For P4, the results of the monsoon season are given to complete the dataset, however, the monsoon season was not part of the FDR correction for P4 (details S4 File).

Fig 5. People’s perceptions on the impacts of environmental and climate change.

Heat map of the perceptions P7–15 (percentages of the answers by the participants are given; p-values from the Chi square test) in accordance with the residential area of the participants in Lowland, Midland and Highland or their general residence in Central Nepal.