Deforestation Impacts on Orographic Precipitation in the Tropical Andes

Eghdami, Masih; Barros, A. P.

doi:10.3389/fenvs.2020.580159

Cited by 4 publications

(3 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Ongoing work seeks to develop a climatology of LDPS by proxy based on large‐scale circulation patterns favorable to moisture convergence at midlevels from ERA5. However, reanalysis does not capture the nonlinear interactions among weather dynamics, topography, and land cover that govern orographic precipitation processes in the eastern slopes of the Central Andes (e.g., Eghdami & Barros, 2019, 2020). Therefore, high‐resolution modeling studies are necessary in the future to elucidate the mesoscale dynamics of LDPS at high elevations.…”

Section: Resultsmentioning

confidence: 99%

“…However, the reliability of this upslope moisture transport depends on moisture convergence along the foothills and low‐level moist entropy. The latter is closely tied to the modulation of atmospheric stability by evapotranspiration from tropical montane forests in the foothills of the Andes (Eghdami & Barros, 2020; Sun & Barros, 2015a, 2015b).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

High‐Elevation Monsoon Precipitation Processes in the Central Andes of Peru

2020

View full text Add to dashboard Cite

Measurements at the high-elevation Lamar Observatory in the Mantaro Valley (MV) in the Central Andes of Peru demonstrate a diurnal cycle of precipitation characterized by convective rainfall during the afternoon and nighttime stratiform rainfall with embedded convection. Wet season data (2016-2018) reveal long-duration (6-12 hr) shallow precipitating systems (LDPS) that produced about 17% of monsoon rainfall in 2016 and 2018 associated with El Niño and La Niña, respectively. The LPDS fraction of monsoon rainfall doubles to 35% with weekly recurrence in 2017 under El Niño Costero (coastal) conditions. LDPS occur under favorable moisture conditions dictated by the South America (SA) Low-Level Jet (SALLJ) and Cold Air Intrusions (CAIs). Backward trajectory analysis shows that precipitable water sustains >80% of seasonal precipitation and ties the LPDS to particular moisture source regions in the eastern Andes foothills 1-2 days in advance, enhanced by increased moisture supply in the midtroposphere. Higher frequency of CAIs and enhanced midlevel moisture convergence along CAI fronts explain the increased LDPS frequency during the 2017 El Niño Costero. These findings highlight the functional role of the Andes morphology in organizing moisture supply to high-elevation precipitation systems on the orographic envelope. Analysis of the Global Precipitation Measurement (GPM) mission satellite-based radar observations points to challenges to precipitation detection and estimation in this region as the GPM clutter-free height (~1-2 km AGL) exceeds the depth of shallow precipitation systems in the MV.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

High‐Elevation Monsoon Precipitation Processes in the Central Andes of Peru

2020

View full text Add to dashboard Cite

show abstract

“…Furthermore, maximum precipitation regions, often referred to as rainfall hotspots, are concentrated along the eastern slopes of the Andes (Chavez & Takahashi, 2017; Espinoza et al., 2015). These rainfall hotspots result from forced convection caused by to the orographic effect of the Andes (e.g., Eghdami & Barros, 2020; Garreaud, 2009; Junquas et al., 2018).…”

Section: Introductionmentioning

confidence: 99%

Performance of Regional Climate Model Precipitation Simulations Over the Terrain‐Complex Andes‐Amazon Transition Region

Gutierrez,

Junquas,

Armijos

et al. 2024

JGR Atmospheres

View full text Add to dashboard Cite

Regional climate models (RCMs) are widely used to assess future impacts associated with climate change at regional and local scales. RCMs must represent relevant climate variables in the present‐day climate to be considered fit‐for‐purpose for impact assessment. This condition is particularly difficult to meet over complex regions such as the Andes‐Amazon transition region, where the Andean topography and abundance of tropical rainfall regimes remain a challenge for numerical climate models. In this study, we evaluate the ability of 30 regional climate simulations (6 RCMs driven by 10 global climate models) to reproduce historical (1981–2005) rainfall climatology and temporal variability over the Andes‐Amazon transition region. We assess spatio‐temporal features such as spatial distribution of rainfall, focusing on the orographic effects over the Andes‐Amazon “rainfall hotspots” region, and seasonal and interannual precipitation variability. The Eta RCM exhibits the highest spatial correlation (up to 0.6) and accurately reproduces mean annual precipitation and orographic precipitation patterns across the region, while some other RCMs have good performances at specific locations. Most RCMs simulate a wet bias over the highlands, particularly at the eastern Andean summits, as evidenced by the 100%–2,500% overestimations of precipitation in these regions. Annual cycles are well represented by most RCMs, but peak seasons are exaggerated, especially at equatorial locations. No RCM is particularly skillful in reproducing the interannual variability patterns. Results highlight skills and weaknesses of the different regional climate simulations, and can assist in the selection of regional climate simulations for impact studies in the Andes‐Amazon transition zone.

show abstract

Regional Land–Atmosphere Interactions in Southern Africa: Potential Impact and Sensitivity of Forest and Plantation Change

Zhang,

Laux,

Baade

et al. 2024

Ecological Studies

View full text Add to dashboard Cite

Southern Africa is experiencing increasing land transformation and natural vegetation losses. Deforestation is one type of this land degradation where there are indigenous forests present, and afforestation of other nature ecosystems with timber plantations. This study performs regional coupled land–atmosphere model simulations using the Weather Research and Forecast (WRF) model with a resolution of 12 km, to assess the impact of forest and plantation cover change on regional climate in southern Africa. Three WRF simulations were designed for different land covers: (i) MODIS-derived land cover for the year 2000 (baseline), (ii) Landsat-based forest and plantation change map during 2000–2015 overlain on the baseline and (iii) theoretical forest and plantations removal relative to the baseline. Modeling results suggest that conversion of forest and plantations landscape to croplands and sparse vegetated land may result in a warmer and drier local climate, increasing daytime temperature by up to 0.6°C during the austral summer, and regulation of energy exchanges by decreasing the latent heat flux. In addition, results suggest that the removal of forest cover in northern part of southern Africa may decrease local precipitation recycling by around 1.2%. While the benefits of conserving native forests are obvious from an ecological perspective, afforestation considerations still require more detailed and local-scale treatments along the soil–vegetation–atmosphere continuum.

show abstract

Deforestation Impacts on Orographic Precipitation in the Tropical Andes

Cited by 4 publications

References 37 publications

High‐Elevation Monsoon Precipitation Processes in the Central Andes of Peru

High‐Elevation Monsoon Precipitation Processes in the Central Andes of Peru

Performance of Regional Climate Model Precipitation Simulations Over the Terrain‐Complex Andes‐Amazon Transition Region

Regional Land–Atmosphere Interactions in Southern Africa: Potential Impact and Sensitivity of Forest and Plantation Change

Contact Info

Product

Resources

About