In recent weeks, heavy rainfall in northeastern Nigeria submerged entire residential areas, displacing tens of thousands of people, destroying farmland and businesses and spreading waterborne diseases such as diarrhea and malaria.

But, as hospitals face a humanitarian crisis in the wake of that flooding, heavy rains have also hampered access to health facilities or even put them out of commission entirely. A major dam burst flooded several hospitals, forcing some to suspend operations, in what authorities say was one of the worst weather events in 30 years.

Nigerian hospitals aren't the only ones seeing challenges connected to extreme weather fueled by climate change. In August, wildfires engulfed towns and villages across the Attica region of Greece near Athens, forcing the evacuation of hospitals.

In May, in the southern Brazilian state of Rio Grande do Sul, thousands of health care employees couldn't get to work because of flooding. Across the state, hospitals canceled elective procedures to deal with the emergency flood response and an increase in infectious diseases linked to stagnant water and lack of sanitation.

By 2100, more than 16,000 hospitals — or one in 12 worldwide — will be at high risk of total or partial shutdown from extreme weather events if fossil fuels are not phased out rapidly, according to climate risk analysts Cross Dependency Initiative.

Many hospitals will have to be moved but some can adapt, according to the analysis. So how are some already dealing with the challenge?

Nigeria's telemedicine approach

Telemedicine might seem relatively new, but it's been around for decades and is gaining importance in Nigeria, as hospitals seek to deal with emergencies fueled by rising temperatures. Health care agencies in the country are opting to partner with virtual medical service providers to help reach those who cannot access hospitals, as was the case for many during the recent flooding.

"We are the quickest response if a natural calamity hits different areas, especially now that we are seeing flooding in Nigeria," Charles Umeh, a public health physician in Nigeria, told DW. "We work in settings of vulnerability where people find it difficult to even transport themselves to where they can access health care."

Umeh told DW that personal experience with floods that submerged his home inspired him to open Parkers Resilient Health, a telemedicine service that can be accessed via the company website or on WhatsApp. 

The physician also runs a mobile clinic that brings health care to the doorstep of vulnerable populations, and is planning to construct a bricks and mortar climate-resilient health care facility.

"We are working with engineers and climate specialists who advise us on how we can install proper drainage systems, and reinforce foundations to withstand water pressure, reducing damage during floods," Umeh said.

Bringing solar and renewable energy to Indian hospitals

As a place people turn to for medical help during flooding or extreme heat, hospitals need a reliable electricity supply to keep operating. But, in India, many, often rural, hospitals face power outages lasting several days, particularly during extreme weather events such as storms and floods.

World Resources Institute India is working with 26 rural hospitals in three states across the country to install solar power, helping to avoid nearly 100 tons of carbon emissions, the organization reports. It's also helped medical staff to treat more than half a million patients who might otherwise not have had reliable access to health care.

"In Assam, India, when a cyclone knocked out power and communication in the entire area for nearly five days, this solar-powered hospital was the only one still fully functional, showing how essential renewable energy can be beneficial during emergencies," Lanvin Concessao from WRI India told DW in a statement.

Rural hospitals in India aren't just using solar to power their facilities, but to cool them, too. In the ancient town of Raichur in southern India, a government maternity center is using solar-powered ceiling fans to offer relief to newborn babies and their mothers during periods of extreme heat, for instance.

India also has guidelines to ensure that health care facilities can remain functional during such disasters, including recommendations to retrofit existing hospitals so they can weather storms and heat waves.

Hospital rooftop farms and green operating rooms in the US

Major extreme weather disasters such as the hurricanes Sandy in 2012 and Katrina in 2005, which brought down power lines and left patients stranded, showed that US hospitals weren't designed to deal with supercharged flooding and storms, according to health and climate NGO Health Care Without Harm.

But facilities such as Boston Medical Center in the northeastern United States have established rooftop farms to help deal with weather extremes. The green spaces, which grow crops like bok choy and radishes that are used in the hospital kitchens and a food pantry for low-income locals, help reduce heat in the facilities, according to BMC. They also slow storm water runoff as plants directly collect and retain rainwater.

Some US hospitals are going further and looking at ways to reduce their carbon footprint. Cleveland Clinic, a health care facility in the Midwestern state of Ohio, is working to make its operating rooms more environmentally friendly by reducing waste, energy use and greenhouse gas emissions. Operating rooms require a lot of energy to run and produce a lot of waste.

"What we do in our hospitals is meant to improve our communities, but our buildings, the materials we use and how we practice can negatively affect people's health," said one doctor involved in the project in a statement, adding that the clinic wants to protect peoples' health by protecting the environment.

Making sure hospitals can still operate in climate-linked extreme weather events isn't enough — the health care sector has to deal with its own emissions too, said WRI India's Concessao.

The sector accounts for 4.4-5.2% of the world's greenhouse gas emissions.

"If built in a climate-resilient manner, hospitals can not only enhance health care service delivery and positively impact patient and staff well-being, but also contribute to ambitious climate change mitigation targets," Concessao wrote.

Edited by: Tamsin Walker and Jennifer Collins