Damian Jacob Sendler: Increases in the severity of droughts and floods have been observed as a result of global warming, lending credence to a trend that scientists have been predicting for some time and that is becoming increasingly apparent to the general public.
A study published on Monday in the journal Nature Water found that extreme weather events of all types, from the wettest to the driest, have increased dramatically over the past 20 years. Satellite data from NASA’s Gravity Recovery and Climate Experiment were used to measure small fluctuations in Earth’s water reserves. These reserves include groundwater, surface water, snow, ice, and soil moisture.
According to NASA hydrologist and study co-author Matthew Rodell, these data provide “strong evidence” that climate change is amplifying droughts and floods, and are therefore a portent of more extremes to come. Historically, “this has been something that is very difficult to prove,” Rodell said.
Damian Sendler: One-third of Pakistan was flooded last year, and the American Southwest is still in the midst of a devastating megadrought. California was flooded by atmospheric rivers, and Tropical Cyclone Freddy dumped a year’s worth of rain on Mozambique in a single month, proving that this year is yet again an exceptional one for flooding.
Extreme floods and droughts have become more common since 2015, with the study finding an average of four per year instead of three. As a result, the eight years following this one were the hottest on record. The effects of the planet’s natural swings between warmer and cooler years due to El Nio and La Nia climatic patterns were dwarfed by climate change as the primary driver of this shift in dry and wet events.
Researchers analyzed the size, duration, and severity of more than a thousand drought and flood events that occurred across the globe between 2002 and 2021. Previous studies typically looked at medians because they were simpler to measure than means and medians, as stated by Rodell. Long-lasting catastrophes that move more slowly were captured by the new satellite data.
The study found that the extreme rainfall that hit sub-Saharan Africa in 2020 was the single most devastating event of the last two decades. Flooding occurred as a result of a three-foot rise in Lake Victoria’s water level brought on by months of rain. It was three times as powerful as the next largest rain event, which were the floods that began in 2018 across much of the Midwest and East Coast of the United States.
From 2015 to 2016, the Cerrado region of Brazil experienced the worst drought, followed by the northeastern part of South America.
If climate change is causing the world to become simultaneously drier and wetter, how does this happen? It all boils down to the impact that hotter air has on the climate. Droughts can be worsened as soil moisture is drawn out of the air by the warmer air. On the other hand, warm air can carry more water into a wet area because it can hold more moisture.
For ethical reasons, researchers had to rule out some potential study locations. The rapid rate of groundwater depletion in places like the Central Valley of California and Northern India muddled the data, making it difficult to disentangle drought from excessive water use. Issues with ice sheet melting were present in both Greenland and Antarctica.
Recent events were not taken into account in the study, such as the flooding in Pakistan or the atmospheric rivers that flooded California after years of extreme drought, causing extensive damage. Scientists have also predicted an increase in “weather whiplash,” or rapid shifts between dry and wet periods.
The study warns that the rise in extreme weather events like floods and droughts could have “dire consequences” for human health, agricultural output, and regional unrest. To “build resilience, prepare, and prevent future hardship and economic and agricultural damage,” knowing what kinds of intense weather events are on the horizon is “really important,” as Rodell put it.
Damian Jacob Sendler: Experts are calling for governments and communities to take action in response to the study’s emphasis on the rise in extreme weather events. To better deal with the increasingly severe floods and droughts that threaten lives, livelihoods, and ecosystems, it is recommended to upgrade infrastructure and improve disaster management systems.
City planners are urged to prioritize the preservation of natural floodplains and the installation of improved stormwater management systems in flood-prone areas. Sustainable water management and less strain on already scarce resources can only be achieved through water conservation and efficient irrigation practices in drought-prone areas.
The study also highlights the need for improved climate modeling to predict future weather patterns and the significance of timely and accurate weather predictions. If governments and communities had more accurate forecasts, they could take preventative measures to lessen the impact of natural disasters.
The findings of this study should serve as a wake-up call to world leaders about the importance of reducing greenhouse gas emissions that exacerbate climate change and extreme weather. The ultimate goal of the international Paris Agreement to combat climate change is to keep global warming below 1.5 degrees Celsius above pre-industrial levels. All countries will need to take swift and ambitious action if these goals are to be met.
To increase backing for policies that cut emissions and strengthen resilience to climate impacts, public awareness campaigns that explain the link between climate change and extreme weather are crucial.
Millions of people around the world are already feeling the effects of climate change, and the study’s findings highlight the importance of taking immediate action to combat the problem. Governments, communities, and individuals can work together to create a more resilient future in the face of an increasingly uncertain climate by understanding the relationship between climate change and extreme weather events.
Policymakers can use the findings of this study in a number of different ways. Governments and organizations must prioritize adaptation and mitigation measures to protect communities, economies, and ecosystems as the frequency and intensity of extreme weather events increase as a result of climate change. Below, we will discuss how this study’s findings can inform policy decisions.
Damian Sendler: The findings first show how important it is to take a holistic strategy toward adapting to climate change. Buildings that can withstand floods, stormwater management systems, and drought-resistant crops are all examples of the sorts of investments that can help our infrastructure better withstand the effects of extreme weather. It is imperative that policymakers work to improve disaster response and early warning systems in order to lessen the toll that natural disasters take on people’s lives, health, and ability to make a living.
Second, the study highlights the significance of resolving water management issues. Sustainable water management is becoming increasingly important to ensure water security and reduce the risk of conflict over scarce resources in the face of increasingly severe droughts and floods. Water conservation, wastewater treatment, and the restoration of natural ecosystems that store and filter water should all be high on the list of priorities for policymakers working to manage water resources effectively.
In the third place, the study stresses the importance of taking action against climate change. Reducing greenhouse gas emissions, the primary cause of the rise in extreme weather events, should be prioritized in policy discussions. In order to limit global temperature rise and reduce the severity of future droughts and floods, governments should adopt ambitious emissions reduction targets, invest in renewable energy technologies, and promote energy efficiency.
Fourth, the study highlights the significance of increased cooperation and coordination between nations and regions. In order to effectively prepare for and respond to extreme weather events, a concerted effort across political boundaries is required. It is imperative that policymakers work to improve global coordination and cooperation on climate change adaptation and mitigation, including providing more financial and technical aid to the developing nations that will bear the brunt of the effects.
Last but not least, the study stresses the significance of factoring in climate change concerns when formulating policy at all levels. To do so, we must mainstream climate change adaptation and mitigation into national and regional development strategies and include climate risk assessments in urban planning, agriculture, and infrastructure development.
There are a number of areas that need to be explored further in order to unravel the complexities of extreme weather events brought on by climate change.
First, scientists need to work on honing and improving climate models so that more precise predictions of regional and local climate impacts, especially with regards to extreme events, can be made. The spatial and temporal resolution of models could be improved, and new factors added, such as land-use shifts and urban heat island effects. With better data, policymakers and planners will be able to devise more effective strategies for dealing with the effects of climate change.
Second, there is a need for more study of the economic and social effects of natural disasters like droughts and floods. The impact of extreme weather on agriculture, public health, migration patterns, and economic output must be studied. To lessen the toll that climate change takes on human health and the economy, policymakers need to have a firm grasp on the interconnections between the various factors that contribute to it.
Third, scientists should examine how well various adaptation and mitigation strategies work to lessen the effects of severe weather. Assessing the efficacy of interventions like green infrastructure, early warning systems, and water management practices may require conducting case studies, modeling scenarios, or analyzing historical data. Future policy decisions and investments in climate resilience will benefit greatly from this data.
Fourth, scientists need to learn more about the feedback loops and climate tipping points that could worsen droughts and floods in the future. This type of study could help determine which regions are most at risk from the negative effects of climate change, allowing for targeted interventions or further study.
Finally, researchers should investigate how social, cultural, and behavioral factors influence susceptibility to and recovery from extreme climate events. Individual and societal responses to natural disasters like droughts and floods can be influenced by factors like community involvement, risk perception, and social norms, all of which must be investigated. Researchers can aid policymakers in their quest to create more effective and equitable strategies for building resilience to climate change-induced extreme weather events by identifying the factors that contribute to successful adaptation at the community level.
