How Climate Change Impacts Weather Patterns?

Let’s first understand the difference between the term ‘Weather’ and ‘Climate’. Weather patterns encompass short-term atmospheric conditions, including rise or dip in temperature, precipitation, wind, and atmospheric pressure. Climate change, on the other hand, refers to long-term alterations in the Earth’s average weather conditions, primarily driven by human activities such as the emission of greenhouse gases.

As our planet continues to grapple with the far-reaching consequences of climate change, one of the most significant and immediate impacts is the alteration of weather patterns. These changes have been the subject of extensive research and study, yielding fascinating insights into the intricate relationship between climate change and weather.

 In this blog post, we will explore the impacts of climate change on weather patterns, discuss experiments that provide valuable evidence, and shed light on recent scientific discoveries in this crucial field.

Impact on weather:

Link between climate change and weather patterns are entwined perpetually and any change in the climate will have the below bearings on weather:

1. Extreme Weather Events Like Rise in Heat Waves

Researchers have conducted numerous experiments that indicate a growing frequency and intensity of extreme weather events like heatwaves, droughts and hurricanes.

Extreme heatwaves occurred in July 2023 in a number of Northern Hemisphere regions, including Southern Europe, China, and the Southwest of the United States and Mexico. Several heat deaths were confirmed in the US, including migrants on the US Mexican border. In Mexico alone over 200 people died due to the heat. Spain, Italy, Greece, Cyprus, Algeria, and China also reported heat deaths, as well as a large increase in hospitalisation due to heat related illnesses. Large parts of the population in Italy and Spain and over 100 million people in Southern US are under heat wave threats too. In all three regions, demand for power spiked and negatively impacted a number of important crops, including olive oil in Spain and cotton in China.

Scientists have employed climate models to simulate how these events would unfold under various emissions scenarios. These experiments consistently reveal a worrisome trend: as greenhouse gas emissions rise, the likelihood of extreme weather events increases.

2. Shifts in Precipitation Patterns

Experiments involving precipitation patterns have also yielded noteworthy findings. Scientists have examined historical data and conducted field studies to show that climate change is causing shifts in precipitation, leading to increased rainfall in some regions and prolonged droughts in others. These changes have serious implications for agriculture, water resources, and ecosystems.

Climate change can significantly affect the intensity and frequency of precipitation. Warmer oceans increase the amount of water that evaporates into the air. When more moisture-laden air moves over land or converges into a storm system, it can produce more intense precipitation—for example, heavier rain and snow storms.

The percentage of the contiguous 48 states’ land area where exceptional single-day precipitation events have contributed a much larger share of the yearly total precipitation than usual is depicted in this image. The line represents a weighted average over nine years, whereas the bars show individual years.

Source of data: NOAA, 20216
Updated online: April 2021

Heavy rain events that cause flash flooding and pass in minutes or few hours are often limited by how much moisture is available to fall as rain. A warmer atmosphere can hold more moisture, so these short duration rain events are intensified in a warming world. As per recent research shows that in Sydney there has been an increase in sub-hourly heavy rain intensity of about 40% over the last 20 years.

3. Changing Jet Stream

The jet stream, a high-altitude wind pattern that influences weather systems, has not been spared by climate change. Researchers have used satellite observations and computer models to demonstrate that climate change is altering the jet stream’s behaviour. This, in turn, contributes to prolonged weather conditions, such as persistent heatwaves or extended rainy periods.

The jet stream is created when warm, southerly air collides with cold, Arctic air, and scientists have long hypothesized that this collision might be weakened by rising temperatures. The temperature differential is narrowing because the Arctic is rising more quickly than the lower latitudes due to climate change. The jet stream may be becoming slower and wavier as a result, which would allow warm air from the tropics to migrate north and get stranded over North America, Europe, and Asia. This would intensify wildfires and cause extreme heat.

Examining weather data from 1979 to 2022, researchers concluded that as snow cover in northern Canada declined, the jet stream grew wavier, allowing warm air to settle over Greenland, hastening ice melt. The findings were published in the journal Nature Communications.

According to the latest research, there is proof that the jet stream is really being distorted by the Arctic’s warming temperatures.

More serious impacts of warming climate.

1. Arctic Amplification

One of the most intriguing recent discoveries is the concept of Arctic amplification. Research has shown that the Arctic is warming at a much faster rate than the global average. This temperature difference between the Arctic and the mid-latitudes weakens the jet stream, which can lead to more prolonged and extreme weather patterns. For instance, a meandering jet stream can trap weather systems for extended periods, causing prolonged heatwaves or heavy rainfall.

Numerous studies report that the Arctic is warming either twice, more than twice, or even three times as fast as the globe on average. Here its shown, by using several observational datasets which cover the Arctic region, that during the last 43 years the Arctic has been warming nearly four times faster than the globe, which is a higher ratio than generally reported in literature. Know more.

2. Atlantic Meridional Overturning Circulation (AMOC) Slowdown

Recent studies have also highlighted the potential slowdown of the Atlantic Meridional Overturning Circulation (AMOC), a crucial ocean current system. A weakened AMOC could influence weather patterns in North America and Europe, leading to changes in precipitation and temperature distributions. This discovery has important implications for coastal regions, including those affected by hurricanes and storms.

Warming generally results in more ocean stratification and enhanced ocean heat transmission due to vertical temperature gradients. Thus, a weakening of the ocean circulation must be the cause of a decrease in ocean heat transport (OHT). Models concur that variations in ocean circulation, particularly in the North Atlantic, determine the response to greenhouse gas warming. At high latitudes, freshwater input is increased and heat loss from the ocean is decreased by a warmer, wetter atmosphere. Convecting water masses thus lose density, decreasing the AMOC. A zone of modest ocean warming that is seen in models and observations is caused by the weaker AMOC reducing OHT in the midlatitudes.

Climate change has ushered in a new era of uncertainty and complexity in our weather patterns. Experiments and recent scientific discoveries continue to shed light on the intricate relationship between climate change and weather, emphasizing the urgency of addressing greenhouse gas emissions and implementing measures to mitigate the impact. As we advance in our understanding of these interconnections, it becomes increasingly clear that the future of our planet’s weather patterns is inextricably linked to our actions in addressing climate change.