As we think of natural disasters, visions of devastating storms, all-consuming tornadoes, and genesis floods come to mind. To farmers, that’s usually the other end of the spectrum that instills the most terror – droughts. They creep in slowly and last for years, causing a lingering impact on agriculture and other major sectors. In the U.S., droughts rank third among the most expensive weather-induced hazards, costing the country’s economy over $9 billion annually on average.

Megadroughts are the worst of their kind. These multi-year streaks of exceptionally dry weather disrupt crop production and water supplies, paving the way for pest outbreaks and wildfires on a massive scale. One such megadrought, claimed by scientists as the most intense since the 800s, has been scorching the country’s Southwest for 24 years in a row, and there’s no end in sight. Unlike a millennium ago, modern farmers have to deal with human-induced climate change, too, which exacerbates drought.

This crop-killing weather forces the farming industry to adapt – by switching to less water-thirsty crops, sustainable cultivation practices, and innovative technologies like the farm crop software EOSDA Crop Monitoring. Let’s look deeper into the agricultural droughts in the USA, their drivers, impacts, and strategies that help growers build drought resilience in their farmland.

What Causes Droughts in the USA

Droughts are complex and versatile phenomena with various consequences, but our focus is on those affecting agriculture and threatening food security. In a nutshell, agricultural drought occurs when soil moisture cannot sustain crops due to below-normal precipitation, extremely high temperatures, or both. It results in substantial crop failure, which also means less forage feed for livestock and, hence, decreased cattle herd.

The bad news is that droughts are inevitable. As scientists concluded from over a millennium of soil moisture observations reconstructed from tree rings, they are part of natural climate cycles. To make things worse, since the early “industrial” 1800s, humans have been messing with climate, releasing whopping amounts of planet-warming greenhouse gases into the atmosphere and disrupting nature’s critical water, carbon, and nutrient cycles.

Agriculture has been trapped within this vicious circle, being the driver of human-induced climate change and the one most affected by it. Resorting to intensive farming practices and mismanaging finite resources to produce more increase global temperatures, triggering adverse weather patterns – including droughts – that hinder production rates. And North America’s history is vivid proof of this.

The horrific 1930s Dust Bowl was the “perfect storm” of natural and manmade factors: the Great Plains’ agricultural topsoils, exhausted by years of deep plowing and deprived of moisture-keeping grasses, were blown away by strong winds amid intense La Niña-driven droughts. The resulting dust storms devastated people and agriculture, causing widespread economic disruption.

Today, the naturally drought-prone American Southwest is torn by an unprecedented megadrought due to an amalgamation of naturally occurring drought, years of poor resource management, and climate change effects – such as intense heat waves and extensive wildfire seasons – which fan the already-high temperatures.

The record-breaking highs observed in 2012 and 2021 across most parts of the U.S. indicate that droughts are becoming more frequent and persistent whenever precipitation and snowpack dwindle. Even the 2023 wet winter, which brought ample rainfall and snowfall to the region, hasn’t fully remedied the crisis, with only some states, like California, managing to break out of the drought.

This unusually dry streak of years would have happened even without us, but it wouldn’t have been as bad. Scientists blame 42% of this megadrought on human drivers. Massive destruction of trees that store moisture and release it back to form rain clouds, intensive farming that increases soil water evaporation, and excessive draining of water bodies for agricultural and residential uses make “things” dryer; not to mention the negative impact on carbon cycling, which is key to global warming and ever-rising temperatures.

Impact of Drought on the U.S. Agriculture

The progressively increasing dry spells and long-term droughts strain the vulnerable agricultural industry and overall food security. The driest years cost the economy billions of dollars: in the 1988-89 drought, the crop losses alone accounted for $15 billion.

One of the immediate effects is a decrease in the quantity and quality of crop yields. To sustain optimal crop growth, plants require specific temperatures and soil moisture levels, which vary throughout the growth cycle. As temperatures climb to extreme levels and scarce or no rainfall fails to provide adequate moisture, crops experience heat and water stress, losing the ability to absorb vital nutrients. Topsoil moisture at the planting stage is essential for proper germination; its lack results in lower plant populations per hectare and reduced yields.

Satellite crop monitoring helps farmers alleviate drought impacts through early detection of stressed crops and timely interventions. This technology also enables more sustainable irrigation water use, which is critical in drought-prone regions.

This leads us to another direct impact of droughts, particularly felt in the U.S.’s arid regions, like California and Arizona – water depletion. Scant precipitation inevitably diminishes surface water and groundwater supplies, leaving less water available for irrigation and increasing its costs. In the past decades, the water levels in the Colorado River Basin, an agricultural “lifeline” that quenches the thirst of over 40 million people and 5 million acres of cropland, have dropped to their lowest, forcing the government to curb allocations for the first time. Since 80% of this water goes to crops and pastures in the Imperial Valley and other agricultural powerhouses, crop growers end up in dire straits.

According to a 2020 study, around half of this precious resource is used for watering alfalfa, the thirstiest and most widespread forage crop grown in the Imperial Valley. During the current water crisis, a clash of interests between city residents and farmers has emerged regarding who should bear the brunt of water shortages.

In fact, both should, as scientists predict a future fraught with droughts. Those farmers who already realize that squandering this precious resource is beyond reasonable are replacing alfalfa with less water-demanding crops and implementing water conservation practices.

It’s worth noting that specialty crops – vegetables, fruits, and tree nuts – are more easily affected by droughts than field crops. In recent years, these crops accounted for 30-40% of the total value of the country’s crops. Therefore, increased specialty crop failure amid drier-than-normal conditions may cause substantial economic losses.

Last but not least, droughts create conditions where pests and diseases thrive. Water-stressed crops are more vulnerable to pathogen attacks. High temperatures stimulate insect reproduction; however, many beneficial insects that kill harmful pests dislike heat. In many cases, this leads to increased pest populations and disease outbreaks.

Tackling Droughts In Iowa’s Corn Fields with Agricultural Monitoring

Weather can make or break the growing season, and considering the erratic patterns observed in recent years, farmers need a better “compass” to navigate its whims. Combining agronomic wisdom with cutting-edge technologies for remote agriculture monitoring is a strategy that helps make better-informed management decisions and secure good yields even in bad years.

In Iowa – the second agricultural powerhouse in the U.S. and leading corn-producing state – the weather wasn’t really a problem for decades known as the “Goldilocks period.” In 2020, though, the lucky weather streak seems to have ended, marked by the onset of drought with below-normal rainfall. Despite the precipitation deficit, the mix of rainfall timeliness, enhanced drought tolerance in genetically developed hybrids, and innovative tech solutions allow the local farmers to maintain lavish yields.

EOSDA Crop Monitoring is a modern remote agriculture monitoring solution that assists crop growers in raising corn with a keen eye for weather conditions. The online platform facilitates overseeing every crop growth stage by providing a diverse mix of farm data on crop health, weather, productivity, soil conditions, and more. Equipped with field insights from the all-seeing satellites, farmers can detect various crop threats, from pest infestations to heat stress, analyze productivity, calculate variable rates for inputs, plan and manage field activities to make farming efficient and sustainable.

In Iowa’s case, this farm crop software is instrumental in the most critical stage of corn development: pollination. Specific weather conditions are required for it to pass successfully, setting the stage for adequate corn yields, such as sufficient soil moisture (without too much rain) and daytime temperatures below 100°F (38°C).

Using EOSDA Crop Monitoring weather graphs for daily and night temperatures and daily and accumulated precipitation, farmers can better understand if their soils received enough moisture and if air humidity is sufficient for proper corn development amid a drought. Holding this moisture is equally important – the changes in crop moisture dynamics over several years based on the platform’s NDMI (Normalized Difference Moisture Index) values can tell a lot about the soils’ water-holding capacity. Lastly, the tool offers an array of vegetation indices for pinpointing drought-related stresses in crops before heavy damage occurs.

Looking back at the past decade, climatologists' frightening claims about a drought-stricken future in the U.S. do not seem overblown. Global food security is on the line, as weather-dependent agriculture feeds the world. Preparedness on all agricultural fronts is a must, with a particular focus on managing water – the most precious asset we can have (or not have) during the most severe and most extended droughts ever witnessed. Everyone, from governments to smallholder farmers, needs to brace for challenging times and embrace modern technologies, which can help withstand the next “Dust Bowl”.