Emerging signals of climate change from the equator to the poles

An international group of climate scientists, led by Professor Matthew Collins and including Fathom’s Dr Natalie Lord, present the results of recent studies into regional climate change impacts and call for urgent action to help communities adapt to the growing risk.

The impacts of human-induced climate change are becoming increasingly clear in almost every part of the world. Monsoon storms are becoming more severe, rainfall and weather patterns have changed and extreme events such as droughts, heatwaves and floods are more frequent.

Even if we stopped producing greenhouse gases today, global temperatures will remain well above pre-industrial levels for many decades, if not far longer. This is due to the long timescales it takes for excess carbon dioxide to be removed from the atmosphere by different processes in the Earth system, as demonstrated in a previous paper led by Dr Lord.

Detailed, accurate information on the local impacts of climate change is crucial to help communities develop effective adaptation measures and protect themselves from the growing risk. In an article for Frontiers in Science, a group of climate scientists synthesize the findings of recent research programs, to create a clearer picture of how regional climates around the world may change over the next century and to identify the knowledge gaps.

The research: What do recent climate models tell us?

Climate change signals are measurable patterns, such as the frequency of heatwaves, that tell us how the climate is changing due to human activities rather than natural variabilities. Climate scientists detect these signals using both observational data and advanced mathematical models that simulate physical processes.

The models use a set of scenarios, known as the Shared Socioeconomic Pathways (SSPs), which sample different possible futures depending on human behaviour factors such as population growth, economic activity and land use. Each SSP scenario is associated with a different potential climate outcome, based on how much the global average temperature warms in response to greenhouse gas (GHG) emissions.

For this article, the researchers reviewed a wide range of recent research which gathered, shared and analyzed the data from multiple regional and global climate models, assessing their climate projections under various scenarios for the next 100 years.

Key findings: regional impacts of climate change

By synthesizing the findings from a range of studies, the researchers presented the following insights about the future regional impacts of climate change.

More intense monsoons

Monsoons are likely to become more intense. Affected regions, especially South Asia, East Asia, and West Africa, will see a higher risk of floods and landslides as well as poorer agricultural yields.

Stronger storms in northwestern Europe

Storm tracks into northwestern Europe may become stronger, leading to an increase in the number of extreme storms and cyclones that make landfall.

More rain and less snow in the polar regions

Precipitation over both poles will change, with more rain and less snow falling, especially in the Arctic, and this is likely to happen much sooner than previously predicted. This could accelerate melting ice and sea level rise.

More frequent and intense El Niño events

The pattern of El Niño Southern Oscillation (ENSO) events will change, with a possible increase in frequency and severity within 20 years. This means we can expect to see more floods, heatwaves, droughts and wildfires in many parts of the world.

Extreme heat and humidity

High temperatures and humidity are likely to increase, especially in tropical and subtropical regions. This could have a major impact on sectors such as agriculture and construction, reducing the ability to work outdoors and reducing crop yields. It can also have a negative effect on human health.

Call to action: Closing the knowledge gap

The climate change signals discussed in this paper point to an increase in regional impacts of climate change in the future. The authors also point to the need for more high-resolution models to close our knowledge gaps, such as our understanding of the complex teleconnections between regional climate signals over long distances.

However, uncertainties should not be a barrier to action. We need to assess the vulnerability and exposure to climate hazards of populations and natural systems, and develop urgent measures to adapt and mitigate risks to economies, health and the environment.