Is climate change affecting our seasonal weather patterns?
Image by Sam Moghadam
Seasonal weather patterns are a part of life. Reliable seasons provide not only temporal markers for events throughout the year, but across the world the security of livelihoods and incomes rely on their constancy.
The effects of climate change mean that seasonal weather is becoming less and less predictable. Some weather patterns are becoming more extended, while others are becoming less frequent. Old models of seasonality are no longer an appropriate way to define weather patterns. Without new modeling and understanding of the timing of seasons, and policy to adjust for the new reality, we risk putting thousands of lives and livelihoods on the line.
Are the seasons really changing?
In short, yes. All across the world, changes in weather patterns and the resulting environmental effects are already having worrying consequences. Seasonal changes refer to the annual variations in precipitation and temperature that affect such as soil moisture, evaporation rates, river flow, and snow cover. Weather refers to the changes in temperature and sunlight on a shorter timescale that are less influenced by the movement of the earth around the sun, and more by atmospheric conditions. Climate change is altering both seasons and weather-- the timing of seasons is changing, and weather patterns are becoming more varied and irregular. Both of these changes have consequences for the natural and built environment.
In the UK, more rainfall is resulting in flooding becoming more frequent, with it being listed in the 2020 National Risk Register as having the potential to result in fatalities and huge economic repercussions. In the United States, routine flooding caused by routine heavy rainfall is also becoming more frequent. Climate Cost Project surveys find that this type of flooding, which often does not reach the level of disaster declaration, causes significant out-of-pocket payments from households. However, it does not get the same public attention or insurance assistance as flooding caused by major declared disasters. This lack of attention results in underestimation of the widespread nature of repeat flooding, particuarticuarly in the Eastern United States.
Alongside flood risks, seasonal changes are also impacting farming practices all over the world. Later and more intense rain seasons across parts of Africa have the potential to affect crops like cocoa and coffee plants. This impact would be felt not only by the farmers who rely on the exportation and sales of these crops to survive, but also by those of us in the West who are consumers of imported commodities. It has also been predicted that by 2050 worldwide yield of crops such as corn, rice and potatoes will all drop, with the predicted corn yield dropping by 20%.
Additionally, unusually warm winter winds are resulting in significantly more winter fires occurring across California. In 2019, the fire season ran from May-November with few fires reported before May and a total of 259,823 acres burned. However, in 2020, the fire season ran predominantly from May-December with many more fires recorded in the early months of the year and more than 4% of the state’s land burned, over 4 million acres, making it the largest wildfire season recorded in California’s modern history. If this change persists, it will raise the question of how appropriate it is to refer to this weather as the “fire season” when in 2020 there were more months that had fires than months that didn’t.
The human consequences of weather becoming climate
Numerous climate organizations are advocating on behalf of those forced to relocate because of the impacts of such changes, known as climate migrants. The Climate and Migration Coalition is an organisation lobbying governments to change attitudes toward climate migrants and to be more receptive to those who need to relocate due to the dangers and effects of climate change. This decade and the next can expect to see ever more climate migration.
In Central America, the increasing frequency and intensity of hurricanes and storms are wreaking havoc on people’s lives and the landscape, with some areas barely recovering from one disaster before another hits. In 2020, Hurricanes Eta and Iota cut through Guatemala, Nicaragua, and Honduras. Many of the communities who bore the brunt of these category 4 and 5 hurricanes relied on smaller-scale agriculture. These disasters decimated the livelihoods of many who were already at risk from other slower-onset hazards. The land will take years to recover from these hurricanes and people in these regions are already migrating away in the hopes of finding a better and safer way of life, in both neighbouring countries and places further afield such as the US.
For those living in wildfire-prone areas, deviances from the regular pattern of fires can have a wide range of impacts. During the California wildfires of 2020, ranchers lost large numbers of livestock to the fires, as well as essential equipment, such as tractors and irrigation systems, being damaged and lost. In some cases, farms lost their entire operation to fires, with buildings, livestock, crops, and greenhouses being completely lost. While naturally occurring wildfires are a vital part of the forest ecosystem of the Western United States, previously these fires occurred much less frequently and more predictably, allowing for those affected to generate income during the rest of the year. An increase in fire frequency and duration upends established practices and leaves ranchers struggling to recover from the damages, let alone adapt to the changes.
Fortunately, communities are already starting to adapt to these changes. Many people impacted are already temporarily migrating for parts of the year to avoid increasing droughts. For example, one migrant who spoke to researchers from the Climate and Migration Coalition described how he leaves Mexico to go to the US to work for three to five months as a safety net against the drought. This allows people to find income elsewhere during the dry season. It’s a temporary relocation, not a permanent move with people intending to return to their initial homes once the season has passed. However, as these changes in the weather become more extreme and commonplace, it is likely that people will be forced to migrate on a permanent basis.
Further, charities such as Practical Action have been working with communities in at-risk areas, helping to both educate and prepare them for future and current effects of weather shifts. For example, a project working in Zimbabwe is tackling the failing crops and resulting malnutrition coming about as a direct result of the effects of climate change. The project focuses on education and preparation, helping those in these areas to be able to cope with changes in weather and also providing information on other crops that could be grown instead.
There are worldwide efforts focused on combating and mitigating the effects of climate change. While many are starting to wake up to the urgency of climate change, to truly reduce the damage of changing weather patterns, we must move faster.
Contributions from Sieren Ernst