No, HAARP can’t create floods, climate change can make heavy rainfall more extreme

Wherever severe floods have struck in the past year, they’ve often been followed up by claims that they’re the result of humans ‘manipulating the weather’. It’s common to see social media users blame the High-frequency Active Auroral Research Program, better known as HAARP, an atmospheric research facility located in Alaska.

Social media users have blamed HAARP for inciting recent floods in Valencia in Spain and New Mexico in the U.S, as well as flooding that struck Dubai and the greater Persian Gulf region earlier this year, in April. Some claims purport that HAARP is responsible for multiple floods at once, implying that HAARP is a central node in some sprawling global conspiracy.

These claims are false, just like the long list of other claims that HAARP is modifying the weather or permanently altering the atmosphere (many of which Science Feedback has reviewed). As we show below, HAARP doesn’t manipulate weather conditions, and it doesn’t have the ability to do so in the first place.

HAARP cannot manipulate the weather or cause floods

HAARP’s main purpose is to study the ionosphere (Figure 1) – the parts of Earth’s upper atmosphere that are ionized, or given electric charge, as they’re bombarded by high-energy electromagnetic radiation from the Sun. HAARP’s antennas can simulate that solar bombardment by temporarily heating up patches of the ionosphere in a manner that scientists can control. Scientists do this to better understand how the ionosphere behaves in different conditions.

That might seem like arcane physics, but it’s actually quite important for modern civilization – many of our communications and navigation satellites interact with the ionosphere, and the solar radiation that strikes the ionosphere can disrupt electronics on the ground during outbursts like solar flares. Although the day-to-day fluctuations of the ionosphere are sometimes called ‘space weather’, that term shouldn’t be misconstrued – they have no direct relation to weather on Earth’s surface.

Nevertheless, since HAARP began operating in the 1990s, it has been the frequent target of conspiracy theories that exaggerate its abilities. These conspiracy claims purport that HAARP can modify the atmosphere to trigger severe weather events (see our recent review debunking other claims that HAARP causes hurricanes). HAARP has absolutely no ability to manipulate the weather.

We can break down why. In order to manipulate the weather, HAARP would need to target the atmospheric layers that do host weather, and those layers would need to absorb HAARP’s radio waves. Most weather forms in the troposphere, the lowest layer of Earth’s atmosphere that ends at an altitude of around 10 kilometers (6 miles). Some weather does begin in the stratosphere, just above that mark, but the lowest part of the ionosphere begins at an altitude of around 64 kilometers (40 miles) – more than five times higher than the top of the troposphere (Figure 2).

Furthermore, even if HAARP was aimed at the lower atmosphere, the radio waves it broadcasts don’t interact with the troposphere or the stratosphere at all. HAARP writes on their website:

 “Radio waves in the frequency ranges that HAARP transmits are not absorbed in either the troposphere or the stratosphere—the two levels of the atmosphere that produce Earth’s weather. Since there is no interaction, there is no way to control the weather. The HAARP system is basically a large radio transmitter. Radio waves interact with electrical charges and currents, and do not significantly interact with the troposphere”

It’s also worth noting that HAARP’s actions are not secretive – HAARP’s scientists publicly announce when and why they’re using the facility, precisely because HAARP’s activities might impact people like astronomers and shortwave radio operators who do use HAARP’s radio frequencies.

Climate change, not weather manipulation, is responsible for worsening floods

Flooding has several potential causes, but the Spain, New Mexico, and Dubai floods all had a common cause: unusually heavy rain. In all three cases, more rain fell in a short period of time than the ground could effectively absorb. With nowhere for the water to go, and with torrential rain piling on even more water, devastating flash-floods ensued. Climate science provides us with plenty of evidence that climate change exacerbates the risks of such floods.

As air warms, it can hold more moisture: a parcel of air can hold 6-7% more water vapor per 1°C increase in temperature¹. That moisture is what falls as precipitation through rain and snow, so increased atmospheric moisture can lead to more rainfall. The Intergovernmental Panel on Climate Change (IPCC) says:

“Human influence, in particular greenhouse gas emissions, is likely the main driver of the observed global-scale intensification of heavy precipitation over land regions. It is likely that human-induced climate change has contributed to the observed intensification of heavy precipitation at the continental scale in North America, Europe and Asia. Evidence of a human influence on heavy precipitation has emerged in some regions”

Climate models show that, across most of the world, the most severe weather events are likely to become even more severe as the world warms² (Figure 2). Another study found that every additional 1°C increase in temperature nearly doubles the likelihood of weather corresponding to today’s most severe precipitation events³.

Heavy rainfall events observed in the past several years have tracked with predictions made by past climate models⁴. We also have evidence that climate change has increased the destructive power of modern-day floods. A study of U.S. floods between 1988 and 2017 attributed 36% of all flood-related damages to “historical precipitation changes”, which models have linked to climate change⁵.

Moreover, we have evidence that climate change contributed to this year’s destructive floods – the same floods blamed on HAARP. World Weather Attribution, a global collaboration of climate scientists, conducted an early analysis of the Spanish floods, which determined that “heavy 1-day rainfall events, as intense as the one observed, are about 12% more intense and about twice as likely in today’s climate, that is 1.3°C warmer than it would have been in the cooler preindustrial climate without human-caused warming.” Another World Weather Attribution analysis determined that the rainfall which caused April’s flooding in the Persian Gulf was 10-40% more intense than it would have been in the absence of recent climate change.

Attributing floods like these to HAARP (or other alleged forms of weather manipulation) can leave audiences with an inaccurate impression of what worsens these kinds of rainfall-induced floods. They can mislead readers into believing that a rise in severe flooding can be blamed on manipulation rather than the very real and worsening effects of climate change.

Conclusion

HAARP’s mission is to study electromagnetism in the upper atmosphere, far above the layer that gives rise to floods (or other ground-level weather). Even if HAARP’s scientists did want to manipulate weather in the lower atmosphere, HAARP’s facilities don’t have the capabilities to do that. Climate science provides clear evidence that climate change, not weather manipulation, is making floods more intense.

References:

• 1 – Tabari H. (2020) Climate change impact on flood and extreme precipitation increases with water availability. Scientific Reports.
• 2 – Fischer et al. (2014) Models agree on forced response pattern of precipitation and temperature extremes. Geophysical Research Letters.
• 3 – Myhre et al. (2019) Frequency of extreme precipitation increases extensively with event rareness under global warming. Scientific Reports.
• 4 – Fischer and Knutti. (2016) Observed heavy precipitation increase confirms theory and early models. Nature Climate Change.
• 5 – Davenport et al. (2020) Contribution of historical precipitation change to US flood damages. PNAS.