What Is Monsoon Season?

Life on Mesoamerica’s Pacific slope is influenced by all kinds of things — from its rich mix of plants and animals to its diverse landscapes and colorful cultures. But one of the biggest forces shaping daily life here is the annual monsoon season.

These rains aren’t just a weather shift. They’re what keep everything going — helping water crops, refilling rivers and underground water, providing drinking water, and keeping forests and wildlife healthy.

At Paso Pacifico, the monsoon season plays a huge role in how we work. It pushes us to respond in ways that make sense for the region. We’ve built our conservation efforts around the rhythm of the rains, because everything we do to protect nature depends on them showing up.

Come along as we dig into what the monsoon season is all about — why it happens, and why it matters so much to local farmers and the tropical ecosystems they call home.

What Is the Monsoon Season?

Monsoons make people think of continuous heavy rains. However, monsoons can create dry periods as well as wet. Technically speaking, the term refers to the definitive shift in directional winds, which typically happens when seasons change. The word was derived from the Arabic word mausim, meaning “season.”

As land temperatures change, so does wind direction. When summer sets in, for example, areas of land heat up more quickly than bodies of water. Warm air rises from the earth, reversing wind direction. Wind then moves from cold to warm places. The hot air condenses and becomes rain.

Are the Rainy Season and Monsoon Season the Same?

They are related. They also share similar qualities. But they have their differences. Monsoons feature changes in wind direction. The rainy season is when the most rain happens. Additionally, rainy seasons can be caused by monsoons. They can also be due to tropical storms and other seasonal factors.

Areas That Experience Monsoons

Asia is well-known for its monsoons. But they can take place in any region that experiences contrasting temperatures between its bodies of land and water. Areas with tropical and subtropical climates, such as the Pacific slope, are prone to monsoons.

Its dry seasons happen from November to April, while wet seasons occur from May to October. Before rains arrive, warm, humid air moves from the Gulf of Mexico and the Gulf of California, converging over Central America’s Sierra Madre Occidental mountains. 

Mesoamerica’s Mid-Summer Drought

During the wet season, Central America and Mexico’s Pacific slope undergo a brief dry period. Scientists call it the mid-summer drought (MSD). In Central America, it is called veranillo, which translates to “little summer.”

The Pacific slope experiences heavy rains at the beginning and end of its rainy seasons. Between these periods of generous rainfall, the area encounters a 2- to 4-week period from July to August when the downpours are less intense, hence the name.

Why the Monsoon Season Matters in Mesoamerica

While monsoon seasons can bring floods and droughts, they are a vital aspect of life in Mesoamerica. 

Aids Agriculture and Food Security

Small Mesoamerican farmers are heavily dependent on monsoon rains for crop cultivation. Indigenous communities who practice small-scale farming are particularly reliant on rain. The changing seasons affect planting and harvesting.

Changes in seasons dictate their planting and harvesting activities. Major crops from the region include:

• Cotton
• Lima beans
• Tomatoes
• Corn
• Chili peppers
• Cacao 
• Avocados

When rain is delayed or reduced, their livelihoods and local food security become threatened.

Replenishment of Water Supplies

Most rain falls during the wet season. Downpours replenish water supplies. They allow rivers to keep flowing. They also maintain balance in natural ecosystems, especially after dry seasons.

The arrival of rain, its duration, and intensity also determine the amount of water available to households.

Supports Power Generation and the Local Economy

Monsoon rains give fisheries and hydroelectric power plants water. This lets the local economy flourish. Belize, Costa Rica, and Mexico generate electricity through water. Five out of seven Central American countries use water to supply over 30% of their electricity needs.

When rains arrive on schedule, economic uncertainty is reduced, while governments and businesses can anticipate and reduce disruptions.

Fosters Biodiversity and Ecosystem Health

The area is biodiverse. It’s home to over 690 types of reptiles, wherein 35% are endemic. Many animals have breeding cycles and other behaviors that are influenced by seasonal changes. 

For instance, frogs lay eggs in temporary water pools. Insects come out after heavy rains, becoming easy prey for bats and birds. Meanwhile, bird eggs hatch after monsoon rains, when food is more accessible. Forests become lush with plant life after downpours, letting animals forage and seek shelter.

How Climate Change Disrupts Monsoon Seasons

Monsoons have been taking place for millions of years. Though the weather changes they bring cause droughts, floods, and landslides, monsoons are not the root of the problem. Rather, it is climate change. 

Long-term changes in weather patterns and temperatures make meteorological events more erratic and intense. Rains are heavier. Winds are stronger. Temperatures change faster while reaching higher and lower extremes that are harder to tolerate.

Destructive Weather Events in Mesoamerica

Disregarding our environment has brought on some of the strongest and most destructive meteorological challenges:

• Honduras faced one of its worst disasters in September 1974. Eight thousand to 10,000 people died from Hurricane Fifi. Another 100,000 were left homeless.
• Hurricane Mitch destroyed millions of homes in Nicaragua and Honduras. Winds reached 180 miles an hour in 1998.
• Hurricane Stan created floods and landslides. Over 1,000 from Guatemala and neighboring areas died in 2005. 
• Category 4 hurricanes struck Guatemala, Honduras, and Nicaragua. More than 400 people died in 2020. Damages were worth $1.4 billion.

Do monsoons cause hurricanes? They don’t, but they can influence their formation and path.

Impact on Conservation

Climate change leads to economic losses. It also reduces the quality of life. Additionally, climate change endangers ecosystems worldwide. The IUCN revealed alarming data. At least 10,967 threatened species are affected by climate change. This makes their extinction more likely.

NASA also shared important information. Even a one-degree rise in temperature has grave and unanticipated effects on species’ abundance, genetics, behavior, and survival. It added that climate change is happening at a rate that’s “unprecedented over millennia.” In fact, the average temperature on the planet has gone up two degrees Fahrenheit since the final decades of the 19th century.

The culprits? Massive carbon dioxide emissions and other human activities. Other examples of harmful human practices include:

• The burning of fossil fuels
• Poor waste management
• Unsustainable manufacturing processes
• Transportation
• Fertilizer use
• Rice cultivation
• Urbanization
• Habitat fragmentation
• Deforestation 

Despite raising the alarm, these types of issues continue to prevail.

Paso Pacifico: Protecting Wildlife Corridors and Fighting Climate Change

Paso Pacifico protects wildlife corridors. We understand the causes and consequences of climate change. We know how it can affect monsoon seasons. These annual events benefit us, our environment, and wildlife. Combined with climate change, however, they can become devastating and lethal forces of destruction. 

We are responding to this urgent issue. Paso Pacifico has initiated reforestation projects and supported innovative efforts like fractal research and the Machete Project.It’s not too late to save the only home we have. But we must take action now.