Southern Africa cyclone, 2023 - Forensic analysis

The UN Global Assessment Report on Disaster Risk Reduction (GAR 2024) report presents 10 case studies, each one with a forensic risk analysis, which systematically examines and investigates the disasters to understand their causes and impacts, as well as the effectiveness of any mitigation measures.

Step 1: Understanding the disaster DNA

What happened?

Tropical Cyclone Freddy was an exceptionally powerful storm with a record-breaking lifespan and strength, as well as an unusual trajectory. Between February 4 and March 14, 2023, it travelled across the southern Indian Ocean from Indonesia to southern Africa, impacting Madagascar, Mozambique, southern Zambia, northeast Zimbabwe, and Malawi. Freddy generated a total accumulated cyclone energy (ACE) equivalent to an entire cyclone season in the southern Indian Ocean.

Freddy set records for its duration and the area it covered. Lasting 38 days overall, it covered 35.5 days and 12,800 km with winds at or above 55 km/h. Meanwhile, its frequent track changes were also unusual. After crossing the southern Mozambique Channel, it circled back to hit the same areas multiple times, generating some of the heaviest rainfall ever recorded. Local reports noted significant storm surges along Madagascar's east coast and in central Mozambique.

By the time Freddy reached Madagascar's east coast, it had weakened to a tropical cyclone with winds reaching 150 km/h at sea and gusts near the centre up to 215 km/h. These areas were still recovering from two previous cyclones that had hit just weeks before.

On February 23, the storm intensified rapidly into a severe tropical storm bringing over 200 mm of rain in just 2 hours to southern Mozambique and the coast, some of the heaviest rainfall ever recorded. Freddy then slowed, reversed direction, and headed back over the southern Mozambique Channel and southern Africa. Parts of southern Mozambique experienced rainfall totals between 400 and 800 mm.

In early March, Freddy strengthened again, circled back over Madagascar, and made a second landfall over Mozambique, where it caused extensive flooding especially in Quelimane and surrounding areas. Around March 13, heavy rains intensified over central Mozambique and Malawi, with rainfall totals between 500 and 1,000 mm over 4 days. One station recorded 1078 mm. The heavy rains in Malawi led to flooding, flash floods, and landslides in hilly areas.

Exposure: Where was the damage concentrated?

Freddy's extreme storm track, strength and longevity - in an already devastating storm season - were key factors in determining its impact.

In Madagascar, many communities were still recovering from two previous cyclones when Freddy struck, exacerbating the damage. Factors such as poverty, poor housing, unplanned development, and deforestation increased these communities' vulnerability.

In Mozambique, excessive rainfall led to severe flooding in places with poor drainage or those below sea level, such as Quelimane. Population growth, land scarcity, rapid and unplanned urbanization and poor housing further increased exposure to the storm's impacts.

Freddy also impacted areas in Mozambique that were typically more prone to droughts and earthquakes but not widespread flooding. The storm presented a new and unfamiliar hazard for these communities, which lacked coping mechanisms and other resources.

In Malawi, deforestation and land degradation heightened the risks of flood and landslide. The southern region, with higher poverty rates, was most affected.

In all affected countries, population growth, poverty and land scarcity have driven people to settle in more hazard-prone areas, perpetuating vulnerability.

Freddy was the second most costly and deadly system in the southwest Indian Ocean after cyclone Idai in March 2019. Economic damages were estimated at $481.5 million in Madagascar, $150 million in Mozambique, and $680.4 million in Malawi, where about 30 percent of the affected population was displaced.

Factors like charcoal use for energy led to deforestation and ecosystem degradation, creating vulnerability to storm surge, erosion, landslides, and flooding. In Malawi's hilly areas, soil erosion had formed gullies, enabling mass debris flows associated with landslides. Linked to poverty, poor construction further increased vulnerability in all affected areas.

Over-reliance on natural resources caused soil erosion and uncontrolled runoff, leading to rapid river level rises and severe floods. Settlements in disaster-prone areas are often a result of generational ties, lack of infrastructure in safer areas and lack of information on past disasters.

Vulnerability: Who was affected and why?

Cyclone Freddy was an unprecedented event that challenged traditional preparedness systems in multiple ways. It caused about 20 deaths in Madagascar, 200 in Mozambique and more than 670 in Malawi, the hardest-hit country.

In Malawi, 659,278 people were reportedly displaced, representing about 30 percent of the total affected population of 2,267,458, according to the Malawi Department of Disaster Management. The affected areas were not accessible by land, so medical and housing assistance was provided via helicopters with help from Tanzania and Zambia.

Population growth, rapid urbanization, and poverty have driven expansion into hazard-prone areas, often resulting in informal settlements. Safer areas were occupied first, but poor and marginalized individuals could not afford land or rent in these areas, leading them to settle in unsafe locations. Poverty also contributed to poor construction quality.

In many places, land-use planning norms, building codes and safety regulations were not adequately applied or enforced. Very few people had insurance against loss and damage from extreme events. While other types of insurance are available in Malawi, Mozambique, and Madagascar, including parametric crop insurance and traditional property insurance, they are not mandatory and remain unaffordable for most of the population.

Freddy's impact was not evenly distributed. Poverty emerged as a key vulnerability factor, with low-income communities in high-risk areas being hit the hardest. Chronic social issues like unemployment and poor health further exacerbated vulnerability by reducing coping capacity and hindering social support networks.

Malawi's updated Nationally Determined Contribution (NDC) estimates that climate change causes annual economic losses equivalent to at least 5 percent of GDP.

Resilience: what factors limited the impacts?

Cyclone Freddy in southern Africa in 2023 demonstrates that "the right mindset" can help avoid disasters. Mozambique showed this mindset through its legislative, policy, and planning framework for tackling disasters, saving many lives through timely warnings, evacuations to safe locations, and readiness at evacuation centres. However, deforestation, poverty, and poor living conditions left many people vulnerable, resulting in around 200 cyclone deaths.

In contrast, Malawi had not made as much progress in adopting the right mindset. Significant deforestation, worse poverty, widespread informal settlements, and a lack of planning and preparedness, led to around 1,200 deaths. The storm also struck during the country's worst-known cholera outbreak.

All impacted countries have legal frameworks and disaster risk management strategies, but their effectiveness needs further investigation. Disaster risk reduction must be integrated into broader policies like land-use planning and environmental management.

Madagascar has a law on National Risk and Disaster Management Policy (Law No 2015-031) as well as a 2016-2030 national strategy for risk and disaster management, which aim to build resilience against shocks. The IFRC and UNDP conducted a case study to assess the impact of these laws and regulations on disaster risk reduction in the country.

Mozambique enacted Law 10/2020 on Disaster Risk Management and Reduction, establishing a legal framework for disaster risk governance. The National Disaster Management Institute coordinates disaster risk management and reduction. A multi-sectoral Disaster Risk Reduction Plan with a 2030 horizon demonstrates government commitment to reducing disaster risk and promoting resilience.

Malawi has draft building regulations and a 2016 Physical Planning Act, but strict codes or laws are not enforced outside cities. Malawi also has a national disaster risk management policy, although its effectiveness needs assessment.

All three countries are members of the African Risk Capacity (ARC) insurance scheme, which provides parametric insurance for extreme climate events. Madagascar and Mozambique received ARC payouts of $1.5 million and $4.4 million respectively.

All three countries have contingency plans based on seasonal forecasts, which consider disaster risks in vulnerable sectors such as agriculture, health, and water. Disaster risk is considered in specific projects in priority areas such as education, health, and infrastructure development. However, efforts to integrate disaster risk management into development planning and climate change adaptation are ongoing in Madagascar, Malawi, and Mozambique.

Risk knowledge remains a major challenge, with limited systematic assessment, documentation, and public awareness. Integrated risk analysis is essential due to the increasing risk of cascading events. Limited knowledge and awareness reduce the ability of at-risk populations to adopt appropriate behaviours for risk reduction.

Malawi lacked enforcement of city building bylaws and guidelines on safer house construction. This resulted in settlements in high-risk areas such as mountain slopes and stream banks.

Environmental degradation and ecosystem service depletion are concerns in all three countries. Laws relating to land use, deforestation, and ecosystem conservation need better enforcement.

Step 2: Future trends

People

• Where infrastructure and transport networks are poor, evacuations become more difficult and costly, even requiring helicopter support.
• Informal settlements in these areas will likely grow as the cost and logistical challenges of relocating to safer areas remain prohibitive for most residents.
• The African Risk Capacity (ARC) Group in 2023 launched a new parametric insurance mechanism to help African countries cope with the devastating effects of flooding. This insurance is already available for Madagascar, Malawi and Mozambique.
• Over the past two decades, southern Africa has seen food import bills increase sharply from $35 billion in 2019 to $43 billion in 2022. The African Development Bank projects that food imports into southern Africa will reach $90 billion by 2025.

Planet

• With median temperatures increases of 1.6°C and 2.2°C by mid-century, more intense and volatile cyclones are expected.
• Like Freddy, these cyclones may become more intense, recurrent, and long-lived, with novel trajectories striking previously unaffected areas.
• While drying is a general projection for the region, IPCC climate models also indicate likely subregional increases in intense rainfall events in eastern southern Africa, including the eastern escarpment regions of South Africa and Mozambique. These changes reflect longer dry spells interspersed with more intense downpours.

Prosperity

• Without urgent risk reduction measures, more intense and volatile storms will continue to undermine investments in infrastructure and sustainable development.
• While the percentage of people employed in agriculture is decreasing in southern Africa, the sector still employs more than 70 percent of the region's poor population.
• Climate change has already caused significant declines in agricultural production in southern Africa. Due to global warming, cereal production in the region has significantly declined over the past decade and is projected to further decline by more than 20 percent by 2030.
• Globally tropical cyclones are among the most harmful extreme weather events, affecting an average 20.4 million people each year and causing mean direct annual economic losses of $51.5 billion over the last decade. The growing empirical evidence suggests that the impacts of tropical cyclones can reduce economic growth in affected countries for more than a decade.

Step 3: Forensic learning

This section aims to encourage dialogue around the forensic analysis to foster improved decision making. The areas for consideration below are envisaged as an input to stimulate in-country discussion and action plan on future disaster prevention and enhanced disaster risk management