The Sky Bears Our Signature, and Dr Refilwe Kai-Sikhakhane is Reading Every Line
- Dimpho Lephaila
- Aug 9
- 6 min read
Dr Refilwe Kai-Sikhakhane’s work lives in the air we all share. In the troposphere, the lowest layer of the atmosphere, where clouds gather, where birds fly, and where every breath we take carries invisible stories of industry, fire, wind, and human activity.
Her recent PhD research focused on nitrogen dioxide (NO₂) concentrations in the Highveld region, around Wakkerstroom in the Mpumalanga province. Her mission was to understand how much NO₂ is in the air, where it comes from, and generate data that others can use to explore what this means for the health of people and the environment they depend on.
To do this, she relied on two observational tools that make the invisible visible. On the ground, a Pandora instrument tracked atmospheric gases by adjusting its view with the movement of the sun. From above, the TROPOMI (Tropospheric Monitoring Instrument) satellite offered a bird’s-eye view of pollution, collecting data in pixels about 5.5 km by 3.5 km, about the size of a small town.
Refilwe used a Pandora spectrometer installed near Wakkerstroom, where it continuously monitored nitrogen dioxide day and night, scanning the sky and the sun at various angles. The data were logged and processed regularly. The two perspectives – ground-up and sky-down – gave Refilwe a multi‑dimensional view of pollution in motion.
Discovering the Hidden Paths of Pollution
Over the course of 24 months, one of the most surprising discoveries in her analysis was that peak nitrogen dioxide levels didn’t occur in the cold, still winter months, when stable air usually keeps emitted gases from travelling far, as expected, but in September. “The transport model also showed that the pollution wasn’t just local,” she explains. “Air masses loaded with nitrogen dioxide emissions from biomass, such as organic matter like trees, grass and crop residues, burning in Swaziland and southern Mozambique were transported to the study site.”
It was a good reminder that what happens in one part of the region doesn’t stay there. Pollution travels, circulates, and eventually settles in communities that had little to no hand in its making, but feel its consequences all the same.
Her research speaks to a bigger truth! Air doesn’t respect borders, and the choices we make, such as what we burn, what we consume, how we power our homes, linger in the sky, enter our lungs, and shape ecosystems far beyond what we can see. This is the signature of human impact, painted across the sky, and Refilwe is reading every line.
What We Don’t See Can Sometimes Still Hurt Us
We can’t see Nitrogen dioxide with our naked eye, but its effects are everywhere. It contributes to acid rain, harms ecosystems, and affects human health in ways that are slow, silent, and serious. “The more we grow as a population, the more resources we use, and the more pollution we emit,” Refilwe explains, with quiet urgency.
Her goal is to make the invisible visible. “I want people to be aware of what’s in the air they’re breathing, to understand how it affects them, and to feel like they can be part of the solution,” she says, firmly and with hope.
Dr Kai-Sikhakhane’s work also contributes to mitigation efforts and policy change. Her research provides the kind of ground-truth data that governments, scientists, and communities alike need to design cleaner, safer, and more just futures.
A Winding Road to Purpose: Science, Shifts, and a Desire for Impact
Refilwe didn't set out to become an atmospheric scientist. Growing up in Pudimoe – a tiny, tucked-away village near Vryburg in the North-West province – she was full of energy, laughter, and big, bubbling questions. She spent her early school years in Vryburg before attending Tiger Kloof Educational Institution, 10 km from Vryburg, also in the North-West province, where she could fully express herself. There, she found the space to join debate clubs, science expos, and any group that sparked her ever-growing curiosity.
“I knew about science, but I didn’t fully understand what it was about. I knew about teachers, doctors and police officers, not scientists.”
While in Grade 12, Refilwe flirted with the idea of becoming a forensic pathologist, until a career guidance visit to Stellenbosch University involving cadavers and preserved foetuses sent her running out of the room, overwhelmed and queasy.
The experience didn’t put her off science entirely, just that particular path.
Her true turning point came later while applying to university. On a form listing potential careers, one word jumped out: scientist. It felt like a calling – a word that stirred something unnamed but familiar. She applied to study science at the University of KwaZulu-Natal, where her journey in the field truly began.
She pivoted to biological sciences and eventually earned her honours and master’s degrees in plant cellular biology. But something was missing.
“I wanted to do work that mattered to ordinary people. Something that could help bridge the gap between academia and everyday life.”
Refilwe's Bold New Chapter in Atmospheric Science
Feeling curious and increasingly restless, Refilwe knocked on a supervisor’s door and said, “I want to work with big data.” Her timing was perfect. She was offered a project in atmospheric science, which was an entirely new direction that allowed her to blend sharp, emerging analytical skills with deep, grounded real-world impact.
The learning curve was steep. She came from a background in plant science, with no experience in coding or large-scale data analysis. But she didn’t let that stop her. “I had to teach myself from scratch. I didn’t even know how to open satellite data files.” There were moments of frustration and doubt, but she kept going.
That first successful attempt – opening and processing real satellite data – was a breakthrough. “That was it for me,” she says. “I was hooked. It was like holding the sky in your hands.”
But there were challenges, too. Efficient data access in South Africa is limited. Storage is expensive, and switching disciplines meant constantly playing catch-up. “What saved me was the community. I had people around me, like my supervisors, family and peers, who were supportive, and who reminded me that I might feel alone, but I’m not.”
A Journey of Self-Belief, Mentorship and Resilience
Beyond the science, Dr Kai-Sikhakhane’s journey is also one of self-belief, mentorship, and resilience. As a woman from a rural community, she knows how rare it is to see someone like her in atmospheric science. She’s determined to change that, to be the face she never saw, and the voice she once needed.
In Grade 10, she was selected for a student exchange programme to Australia, a trip that cracked open her world. “I always think about that,” she says. “Ngwana waMotswana from a village in South Africa... now working with satellite data. That alone tells me it’s possible.”
Her story is proof that science isn’t reserved for the few. It belongs to the curious, the bold, the ones who dare to ask.
Outside the lab, she’s just as grounded. Refilwe loves cooking, skipping rope, and reading novels. She also gives back by mentoring, tutoring, and encouraging others on their science journeys, reminding them that they, too, belong here. As part of this passion, she founded Marang a Kitso, a tutoring and research support company whose name means Rays of Knowledge, a name that reflects her deep belief in helping others grow, shine and find their way through learning.
Dr Kai-Sikhakhane’s Guiding Wisdom
For aspiring scientists, Refilwe has one key message: It’s not that deep. Just be consistent, and you’ll get there.
She smiles as she says it, but she means it. “You won’t change the world overnight. But your research matters. And if you don’t love what you’re doing anymore, that’s okay. You can change paths.”
Her story is proof of that, a story of changing directions, staying curious, and turning questions into knowledge. And through it all, she’s driven by one purpose: to understand what’s in the air we breathe, where it comes from, and how it’s shaping the health of our communities and the planet we depend on, because only when we see the full picture can we begin to change it.
Connect with Refilwe on LinkedIn.
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