Tag: heavy rainfall

False, Phys.org, West Africa’s Heavy Rains Aren’t Unusual or Due to Climate Change

A recent post at Phys.org, “Climate change makes extreme West Africa rainfall five times likelier, study finds,” relies on a weather attribution study to assert that recent heavy rainfall and subsequent flooding in West Africa was made more likely to occur in what the attribution group calls “a pre-industrial climate.” This is misleading.

From ClimateRealism

By Linnea Lueken

A recent post at Phys.org, “Climate change makes extreme West Africa rainfall five times likelier, study finds,” relies on a weather attribution study to assert that recent heavy rainfall and subsequent flooding in West Africa was made more likely to occur in what the attribution group calls “a pre-industrial climate.” This is misleading. History shows heavy rains and flooding are not uncommon across West Africa. The regional rainy seasons are driven by a combination of factors, including long-term ocean patterns and the West African monsoon.

Citing claims from World Weather Attribution (WWA), a climate activist group formed specifically to link climate change to weather events, Phys.org says that heavy rain was once considered rare and is getting worse. This is false. Seasonal heavy rain is a characteristic feature of the regional climate pattern. Although recent decades might be seeing a local (albeit sporadic) trend towards more heavy rains, it’s largely due to recovery from a larger multi-decadal climate pattern. In addition, even WWA’s authors admit that urbanization and land subsidence have a large impact on flooding that cannot be blamed on climate change alone. This means that human interventions can have a significant influence over any potential danger posed by weather, whether or not warming has anything to do with it.

The Phy.org post reports on May and June’s heavy rainfall in West African coastal countries, from the Ivory Coast to Nigeria, which led to deadly flooding and structural damage. Phy.org cites WWA, which wrote that “climate change driven by human greenhouse gas emissions had increased the likelihood of the rains that caused the floods while also boosting their intensity by between 4% and 23%.” WWA goes on to claim that the events were “once considered rare” but now are “expected every two or four years in the region.” It should be noted that 4 percent and 23 percent are very different, this is a massive range of uncertainty.

The study relies on the idea that warmer air holds more moisture, and thus leads to heavier rainfall. Although this is true in general, in isolation from local conditions, there are multiple problems with this simplistic model as it is presented in the mainstream media. The maximum amount of water vapor the air can hold does go up with warmer temperatures—under certain pressure conditions. Temperature highs do not correlate directly in all scenarios with precipitable water and humidity. For example, 100℉ temperatures in the high plains desert does not lead to heavier rainfall than 90℉ temperatures in Florida.

Topography also impacts rainfall: orographic lift describes when air is driven up the side of a mountain, on the windward side where the air is rising, moisture condenses and precipitates out. There will be heavier precipitation on the windward side, which in West Africa is on the side of the coastal villages.

June is the rainiest month for West African coastal cities by far. Lagos, Nigeria, for instance, has historically experienced a significant jump in rainfall average from May to June. (See chart below)

Figure 1: Chart from https://era-explorer.climate.copernicus.eu/?lat=6.39&lng=3.10&plot=0

In the North region of West Africa, countries like like Mali, Niger, and Burkina Faso, experience a three-month rainy season annually, typically running from July through September. The coastal countries in Southern West Africa, Ghana, Togo, Benin, and Nigeria, experience two rainy seasons, April through July and a shorter rainy season in September to October.

Across the region, these rainy seasons are driven by a long-term climate pattern called the Atlantic Multidecadal Oscillation, which drives changes in sea surface temperatures over several decades, swinging from negative (dry) phases to positive (wet) phases. A 2025 study published in Springer’s Bulletin of the National Research Centre finds that the current trend towards more “extreme” rain has only been happening since the AMO entered a positive phase in the 1990s, but before that was suffering from very dry conditions caused by previous negative AMO:

The Atlantic Multidecadal Oscillation (AMO) is one of the key drivers of long-term rainfall variability in West Africa.

Different studies have pointed out that rainfall variability in the tropics, including Nigeria, is an important factor due to complex interactions between global and regional climate drivers such as the El Niño–Southern Oscillation (ENSO) and the Atlantic Multidecadal Oscillation (AMO) (Ogunrinde et al. 2024; Okonkwo et al. 2015). South-Western Nigeria has transited from the negative AMO period of the 1980s and early 1990s with aridity to the favourable AMO period of the late 1990s to the current with more frequent extreme rain events (Zhang et al. 2021).

WWA’s study looks at the Gulf of Guinea region, which includes several countries, averaging out “extreme precipitation” over the entire area, which necessarily ignores regional and local differences. But, of course, a nuanced description of conditions on the ground undercuts the assertion that global warming alone has led to a widespread, general increase in precipitation. This is typical of the type of advocacy driven, rapidly produced work released by WWA, as Climate Realism has discussed in multiple posts before.

In fact, various studies come to different conclusions. Each study uses a different kind of statistical analysis, and it is notable that even within a single country the trend in extreme rainfall varies regionally.

WWA admits that the rainfall in Ghana was not unprecedented, with June rainfall being described as the “highest level since 1995.” What they also admit in the very first bullet point of their press release, an acknowledgement that Phys.org devotes only a part of a single sentence to, is that urbanization plays a big role in the dangerous flooding itself.

All Phys.org reports is that the researchers “said fast-growing coastal cities were particularly vulnerable because of rapid urbanization in flood-prone areas.” But WWA was more explicit, writing “rapid urbanisation and the expansion of formal and informal settlements into floodplains and conversion of natural vegetation to croplands have reduced natural drainage capacity and increased exposure to flooding.”

Deforestation both for agriculture and urban expansion is a big problem across West Africa. This contributes to flooding in two ways. First, forests slow the flow of precipitation allowing it to seep into the soil where it is used by the trees and underbrush. Second, denuded soil, when not simply washed away, becomes hardened and compacted in the heat, meaning when rain falls it runs swiftly into streams and rivers, increasing flooding.

Here, WWA accidentally highlights (and Phys.org buries) the main issue, the actual danger to human wellbeing in the region. As Climate Realism has pointed out previously (here, here, and here), flooding in urbanized parts of West Africa and other parts of Africa is largely due to poor urban planning, the infilling of wetlands, lack of water handling infrastructure, and often careless deforestation. Towns that are destroyed by floods are rebuilt without accounting for potential future weather disasters, even when an area is known to be in danger from heavy rainfall. Scientists and urban planners have pointed out that bad water handling infrastructure greatly exacerbates flooding from heavy rainfall, regardless of climate change.

The good news is, these are problems that can be fixed, unlike the weather itself.

Phys.org, among other media outlets, love latching on to the climate change related claims made by alarmist groups like WWA, while downplaying contributing or leading factors that can result in ordinary cyclical weather patterns hitting people and communities harder. It is lying by omission and needs to stop. Until reporting becomes more honest, perhaps audiences should stop listening.

No, AXIOS, the Dubai “Rain Bomb” Has No Ties to Climate Change

An article written by Andrew Freedman, titled “Dubai’s record-shattering “rain bomb” has clear climate change ties,” published April 17th, in the online news website AXIOS makes the claim that record rainfall received in one day in the city of Dubai United Arab Emirates (UAE), has a clear connection to climate change. This is false.

From ClimateRealism

By Anthony Watts

An article written by Andrew Freedman, titled “Dubai’s record-shattering “rain bomb” has clear climate change ties,” published April 17th, in the online news website AXIOS makes the claim that record rainfall received in one day in the city of Dubai United Arab Emirates (UAE), has a clear connection to climate change. This is false. Not only is AXIOS conflating weather events with long term climate change, other evidence suggests this was little more than a rare weather event, which has happened before according to weather history for the area, and weak city drainage infrastructure was unable to handle the excess water.

The article notes the heavy rainfall and poor drainage stating:

  • At least two years’ worth of rain, or about 6.26 inches, fell in just 24 hours, qualifying as what have come to be known colloquially as “rain bombs” for their ultra-heavy totals in such short periods of time.
  • This amount of rainfall in a single day would cause problems even in more temperate locations, let alone Dubai, a desert city with poor drainage.

With over 6 inches of rain in a short time in a desert city that is not known for having infrastructure designed for large amounts of rain, it is not at all surprising that the drainage infrastructure could not handle an event like this, leading to street flooding. Freedman’s article goes on to say that the heavy rainfall event was forecasted by weather models:

The proximate cause of the flooding was a slow-moving and potent area of low pressure, or cold pocket of air aloft, that sparked complexes of severe thunderstorms over the United Arab Emirates and nearby countries on Tuesday.

This storm system, along with the threat of heavy rainfall, was shown by weather models several days in advance.

That is certainly true, for example in Figure 1 below, the ECMWF weather model output for April 16th shows significant rainfall for the area, with forecast color zones in excess of 6 inches.

Figure 1 – Forecast rainfall for the UAE on April 16th, source: weathermodels.com

Since the forecast showed significant rain over the area, UAE’s cloud seeding program apparently was put into action according to this article on Newsable:

Since the 1990s, the United Arab Emirates (UAE) has been actively engaged in cloud seeding efforts, overseen by the National Center of Meteorology (NCM). This government agency manages the country’s Rain Enhancement Program, utilizing a network of numerous weather stations to closely monitor atmospheric conditions for seeding operations.

Ahmed Habib, a specialist meteorologist at NCM, revealed to Bloomberg that seeding planes conducted seven missions over two days leading up to the heavy rainfall that inundated parts of the desert nation.

It seems like a simple case of a rare and intense short-term rainfall event, possibly juiced by cloud seeding. Since short-term weather models were used to forecast it, climate does not enter the picture. Long-term climate models could not have forecasted such an event because it is well below their time-scale of years to decades ahead.

Where Freedman’s article goes off the rails is with this claim:

Instead, climate science studies and observations around the world show that extreme rainfall events like this, including ones that break all-time records, are becoming more common and severe as the planet warms.

Moisture from the warm Persian Gulf fed into the thunderstorms in this case.

In fact, increased hydrological extremes, in both the form of drought and heavy rains, are one of the most robust ties to human-caused climate change, which is reshaping global weather patterns.

Freedman’s conflation of a single day weather event with long-term climate is his first error. Weather is not climate. Further, his claim on hydrological extremes is baseless, because the latest scientific report from Intergovernmental Panel on Climate Change (IPCC) shows clearly that there is no linkage to climate change at all. Figure 2 shows Table 12.12 on Page 90 – Chapter 12 of the UN IPCC Sixth Assessment Report. Emergence of Climate Impact Drivers (CIDs) in time periods shows this. The color corresponds to the confidence of the region with the highest confidence: white colors indicate where evidence of a climate change signal is lacking or the signal is not present, leading to overall low confidence of an emerging signal.

The section on heavy precipitation is highlighted in yellow. Note that the white spaces in the table for heavy precipitation indicate that such events have not emerged in the present, nor are they expected to emerge by 2050 in the context of long-term climate change. See the key at the bottom for the meaning of all colors.

Figure 2 – Table 12.12 | on Page 90 – Chapter 12 of the UN IPCC Sixth Assessment Report. Emergence of Climate Impact Drivers (CIDs)

Obviously, climate science does not support the claims made by Freedman and AXIOS about Dubai rainfall and flooding.

This shameful rush to judgment blaming climate change in the media is part of a pattern we have observed time and again here at Climate Realism. Almost without fail, when there is some oddball or unique weather event anywhere in the world, climate alarmists and the media immediately rush to blame it on climate change whether they have any facts to support it or not. Such behavior is irresponsible journalism.