Luca Lombroso, Meteorologo Osservatorio Geofisico di Modena DIEF UNIMORE, volontario Foreste Per Sempre OdV
Although this period is typically characterized by the dry season, unexpected rainfall has affected late December in Montezuma and the Karen Mogensen Reserve in Costa Rica. Over several days, frequent showers have interrupted brief pauses, leading to substantial accumulations that have significantly impacted the landscape and vegetation.
At the Karen Mogensen Reserve, webcam images show a persistently overcast sky and surprisingly lush vegetation for the dry season. This suggests that heavy rains are maintaining moisture levels akin to those of the rainy season.
Meteorological Causes of an Anomalous Phenomenon
The persistent rainfall is caused by a blend of meteorological elements:
- Gentle Trades: The winds typical of the dry season are unusually mild.
- Intertropical Convergence Zone (ITCZ): Positioned further north than usual, it is helping to channel moist air into the region.
- Weak Depressions: One over the Caribbean Sea and another in the Pacific Ocean are further destabilizing the atmosphere, promoting the development of rain.
The atmospheric humidity maps between 850 and 300 hPa confirm the presence of extremely moist air in the area, a key factor in explaining the persistence of precipitation.
Forecast for the Coming Days
In the next few days, forecasts predict longer breaks in rainfall and the chance of more extensive clear skies. Despite this, humidity levels may stay elevated, resulting in occasional showers until January 2-3. Following this period, trade winds are anticipated to strengthen, likely restoring the stable conditions characteristic of the dry season, though some variability may continue.
Situation at the Italia-Costa Rica Meteorological and Biological Station
The weather station at Karen Mogensen Reserve is temporarily offline awaiting both routine and extraordinary maintenance, alongside a major overhaul planned for January 2025. This essential operation aims to resume uninterrupted climate data collection, vital for enhancing our understanding of these unusual phenomena.
The station is set to become operational soon, poised to deliver valuable insights for monitoring a region that is both precious and vulnerable to climate change.
Conclusions: A Sign of Climate Change?
The occurrence of unseasonal rains may be intensified by the ongoing impacts of climate change. Such extreme events underscore the critical need for systematic monitoring and in-depth study of tropical environments.
Stay tuned for more weather updates and insights on the climate and happenings at the Karen Mogensen Reserve. Pura vida! 🌴🌧️
