Short Wave

Why The Tropics Have A Weather Forecasting Problem

October 10, 2025

Key Takeaways Copied to clipboard!

  • Weather forecasting models are historically biased toward mid-latitude dynamics, leading to significantly less accurate predictions for tropical regions where moisture, not temperature variability, is the primary driver of weather patterns. 
  • Atmospheric scientist Ángel F. Adames-Corraliza's research, which earned him a MacArthur Fellowship, focuses on the critical role of water vapor (humidity) and the coupling of moisture, rain, and wind in tropical weather systems like the Madden-Julian Oscillation (MJO). 
  • The lack of a comprehensive, mature theory for tropical atmospheric dynamics, unlike that for the mid-latitudes, results in a human safety and well-being issue because extreme tropical events are not predicted as effectively. 

Segments

Host Introduction and Feedback Request
Copied to clipboard!
(00:00:16)
  • Key Takeaway: Short Wave encourages listeners to leave ratings and reviews on podcast platforms to provide feedback.
  • Summary: Host Emily Kwong opened the episode by asking listeners for feedback via ratings or reviews on their listening platforms. The host emphasized that listener feedback is taken seriously. The segment was preceded by sponsor messages from Memorial Sloan Kettering Cancer Center.
Angel’s Hurricane Experience
Copied to clipboard!
(00:00:48)
  • Key Takeaway: Experiencing Hurricane George in 1998 deeply impressed Ángel F. Adames-Corraliza, driving his later career focus on tropical meteorology.
  • Summary: Ángel F. Adames-Corraliza grew up in San Sebastian, Puerto Rico, and recalled the intensity of Hurricane George in 1998, noting the inability to evacuate from the island. The memory of the roaring winds and shaking house left a lasting impression on him as a child. This experience became a driving force behind his pursuit of a PhD in atmospheric science.
Impact of Hurricane Maria
Copied to clipboard!
(00:01:54)
  • Key Takeaway: Hurricane Maria in 2017 reinforced Adames-Corraliza’s desire to understand tropical weather drivers to better serve his community.
  • Summary: Hurricane Maria in 2017, noted as the 10th most intense Atlantic hurricane on record, was a life-changing event for Adames-Corraliza, causing weeks of lost contact with family. This storm fueled a greater desire to understand the fundamental forces driving tropical weather and climate. He felt a strong drive to return to Puerto Rico or similar communities to share essential meteorological knowledge.
MacArthur Fellowship Recognition
Copied to clipboard!
(00:03:07)
  • Key Takeaway: Adames-Corraliza was named a MacArthur Fellow for popularizing the key role of water vapor in tropical weather and climate.
  • Summary: Adames-Corraliza’s research highlighting humidity’s role in the tropics earned him a MacArthur Fellowship, unofficially known as the Genius Grant. He expressed that receiving this recognition was significant for Puerto Rico, a community often recognized for arts but rarely for science. The award signifies that his community’s contributions are seen and valued.
Mid-Latitude vs. Tropical Weather
Copied to clipboard!
(00:06:02)
  • Key Takeaway: Mid-latitude weather variability is driven by the jet stream’s undulations (troughs and ridges), while tropical weather is primarily driven by humidity fluctuations.
  • Summary: Historically, atmospheric research focused on mid-latitude countries like those in North America and Europe, where weather changes dramatically due to temperature swings. In the tropics, temperature variability is minimal; instead, weather patterns alternate between periods of high humidity (rainy) and dryness. The mid-latitude jet stream is governed by geostrophic balance and the Coriolis force, creating day-to-day temperature changes.
Historical Tropical Knowledge Gaps
Copied to clipboard!
(00:07:10)
  • Key Takeaway: While indigenous populations held specific knowledge of major tropical phenomena like hurricanes and El Niño, Western scientific models largely ignored the tropics until World War II.
  • Summary: Indigenous populations, such as the Taino (who named the entity ‘Huracan’) and Peruvian natives (who knew of El Niño), possessed knowledge of major tropical events. Western understanding was limited until World War II, when combat in the tropical Pacific revealed the substantial scale of tropical weather changes. Herbert Riel’s 1950s book marked an early attempt by a Northern Hemisphere scientist to document tropical meteorology.
Forecasting Deficiencies and MJO
Copied to clipboard!
(00:11:28)
  • Key Takeaway: The absence of a comprehensive tropical theory means most forecasting models fail tropical residents, whose safety depends on accurate predictions of floods and heat waves.
  • Summary: The lack of a comprehensive theory for the tropics, compared to mature mid-latitude theory, results in forecasting models that are ill-equipped for tropical events. This deficiency negatively impacts human safety and well-being in tropical regions due to poorly predicted extreme events. Adames-Corraliza’s early work focused on the Madden-Julian Oscillation (MJO), a massive, slow-moving tropical phenomenon comparable in importance to El Niño.
Moisture Feedback Loop
Copied to clipboard!
(00:13:28)
  • Key Takeaway: Tropical phenomena like the MJO are driven by a recurring feedback loop where wind patterns move moisture, and subsequent rain alters those wind patterns.
  • Summary: Studying the MJO led to the realization of how water vapor is crucial in tropical rainfall. The MJO’s movement is explained by the coupling of three elements: moisture, rain, and winds. This coupling creates a feedback loop where winds move humidity, rain changes the winds, and this cycle propagates the phenomenon eastward.
Future of Tropical Forecasting
Copied to clipboard!
(00:14:39)
  • Key Takeaway: The goal for atmospheric scientists is to achieve equal representation in climate reports and forecasts so that all global regions receive the best possible prediction accuracy.
  • Summary: Adames-Corraliza advocates for a future where climate reports and forecasts equally represent and do justice to all regions globally. Currently, knowledge about the atmosphere is not equally distributed across the globe. The aspiration is to reach a point where everyone knows the same amount about the atmosphere everywhere.