A Tale of Two Fields
Told in Degrees Celsius

A Life of Science: A Series by New Scientists

As temperatures climb, solutions that protect both crops and those that tend them are needed.

  

VViewing Arizona from above, it’s clear how closely life follows the path of water. Trails of green run through valleys and small gullies cut cleanly into the surrounding shades of ochre and rust. On the ground, row after row of carefully cultivated crops almost shimmer against their desert backdrop. This contrast makes visible the precarity of life here. A delicate balance between sun and water, life and death; a knife’s edge illustrated in the landscape and the scenery. Here, the very environment testifies to the power of shade and exposure. Twin forces that draw the line between life flourishing and failing.

I step out of the car on a summer’s morning, 30 miles north of Tucson. The sun barely peeks above the horizon and yet heat begins to prickle my back. I’m two years into my PhD studying desert agriculture, but the intensity of Arizona in July still catches me off guard. I pull on my hat, blocking the molten rays of morning light, and head over to my lab group, which stands in a huddle. Straws are drawn for who works where. Those drawing short straws head left towards a neat block of crops already turning their heads towards the dawning sun. The long straws retreat to my right, to the still sleeping plants sheltered by a canopy of solar panels. This is agrivoltaics, a fancy word for a simple idea: growing crops beneath a solar array. It’s a sight our research lab has become accustomed to—rows of spinach, kale, and cowpeas thriving under the raised grid of solar panels. It’s funny how quickly the extraordinary becomes ordinary. Now this shaded space where tradition meets technology only stands out as the plot in which we all hope to work, particularly in summer.

In the desert, the heat wraps around you fast. I pull on clothes to keep the sun off my skin, opting to be slowly baked through layers of fabric. I head left toward the open field of kale. Even now, the morning sun bathes their leaves. Unlike my colleagues who drew straws, my research requires I work in both fields today. With the knowledge that the relentless sun will soon make the exposed plots hard to bear, I always tackle them first. Moving between rows, I check my network of microclimate sensors—instruments that capture how intense the sun is, how hot the air is, how quickly sweat might evaporate. I check wiring and connections, ensuring each instrument is correctly calibrated and steadily feeding data to its logger. The longer I work, the softer the edges of my mind become, its sharpness dulled by the sun.

“At least it’s dry heat.” The desert dweller’s mantra echoes through my head as heat snakes around my limbs, pulling tighter as time wears on. The unforgiving desert climate affects my concentration, making constant vigilance necessary. Checking and double-checking my work becomes my personal mantra as I struggle with the humidity sensors. Here, mistakes are revealed by the sun, crafted in it. Grateful that my heat-addled mind will result in no more than incorrect data or a loose wire connection, I think of those beyond our research plots. Of the farmworkers who can’t afford to slow down, battling heavy machinery or racing against piece-rate pay. A mistake for them can be far more costly. Their lives and livelihoods are paired so closely with this sun-soaked environment.

Farming has always been challenging in the Southwest, but with each passing season the demands of the land grow heavier. Temperatures soar, droughts lengthen, water seems to fade further from memory. The once-mighty Colorado River, the lifeline of seven states, runs thin. Its reach shrinks away like a noon shadow. Even as federal water managers and state authorities reconsider water rights and begin to shift allocations under the weight of this crisis, more and more fields that stood productive for generations lie fallow. Whole families are forced off their lands as the new realities of farming in these conditions settle.

In creating shade where it’s needed most, I hope this work helps sketch out the blueprints for fairer farming in a hotter, drier world.

If you speak to the farmworkers who cultivate these lands, you’ll hear a range of stories. “It’s always been this way,” some insist. Others speak emphatically about how much hotter it is getting, how the rain falls less frequently. Beneath these differing accounts runs a common undercurrent. It’s clear the conditions in the Southwest are pushing agriculture to its limits. Farming isn’t just challenging out here, it’s potentially deadly. This harsh reality calls for a fundamental rethinking of how agriculture is approached here, and in similar arid regions around the globe. As temperatures climb, solutions that protect both crops and those that tend them are needed. And it’s for this reason I find myself checking equipment in the company of kale and cowpeas, amid the Arizona summer.

Satisfied with my instruments and the data being collected under direct sunlight, I head towards the respite of the agrivoltaic structure. The panels throw a mosaic of shadows across the field. Diligent researchers occupy each patch of shade. As the sunlight shifts throughout the day, so too do they, tracing comfort across the space. The plants thrive here, a palette of green almost entirely obscuring the brown. They grow so densely in some places that it is difficult to collect data from the right plant. Glancing back out towards the smaller sun-drenched crops, the surroundings seem to almost swallow them up. The difference is stark, verging on comical, its obviousness seeming almost staged.

I find my own patch of shade and envelop myself in it, immediately grateful as the channel of direct heat is severed. I repeat the same movements as before, examining the wiring of humidity and temperature sensors, checking the placement of a black globe that records how much aggressive sun the plot endures. But this time, the agrivoltaics shelter me from the harshness beyond. It’s shocking how much difference the shade can make, how much longer you can work, how much clearer your head feels. And it’s that very difference that all my equipment is trying to capture: the striking contrast you’d immediately feel if you stood among the plants in both our fields.

The science behind this altered environment is surprisingly simple. The panels prevent a portion of the intense sunlight from reaching the ground and reduce the heat experienced by the soil, plants, and people below. They create a microclimate—a bubble beneath the panels that’s often several degrees cooler than the surrounding fields. For our crops, this means less water is lost, allowing them to grow bigger and stronger. For farmworkers, this small reduction of a few degrees Celsius can mean the difference between life and death.

As I finish up my day’s work, I drain what’s left of my water, assured the data is collecting as it should. With each passing minute, the numbers captured by instruments passed through to dataloggers paint an increasingly vibrant image of the difference between the two fields: lower temperatures, higher humidity, less intense sunlight. Each datapoint sharpens the image into focus. Questions still echo in my mind about scaling this technology, about ensuring it reaches those who need it most. But standing in the shade of this agrivoltaics structure, feeling its protection while watching crops thrive beneath it, I can’t help but see a future where we don’t have to choose between feeding people and protecting those who work the land. In this way, my research isn’t just observing the delicate interplay between sun and water, life and death, it’s seeking ways to tip that balance. In creating shade where it’s needed most, I hope this work helps sketch out the blueprints for fairer farming in a hotter, drier world.    

Walking back to the car, I trace a finger along a kale leaf beneath the panels. It’s verdant, unblemished, alive. It’s the same plant I tend in the open field yet visibly transformed by this gentler environment. Like the researchers who move from shadow to shadow, these plants have found refuge in the simplest of solutions—a barrier between them and the relentless Arizona sun.

Standing in this pocket of protection while watching this single leaf thrive beneath it, I witness something immediate and tangible. A small victory, where the knife’s edge between heat and growth, hardship and possibility, has been momentarily blunted by the shadow of an agrivoltaic panel.