In 2009, a group of scientists published a list of nine systems they believed were necessary for a healthy planet. These essential items included biodiversity, ocean acidification, the ozone layer, freshwater use, land-system change, biogeochemical flows, novel chemicals, climate change and atmospheric aerosols.
Based on current research, these scientists believed the Earth would continue to be stable as long as healthy boundaries were respected in these nine areas. However, these systems are interconnected so closely that change in one section has the potential to disrupt the others.
Take atmospheric aerosols, for instance. These tiny particles come from natural and artificial sources. Recent research suggests they directly impact weather and temperature and may be influencing changes in Arctic climate and biodiversity.
What are aerosols?
When you hear the word “aerosols,” you may think of hairspray or spray paint. However, in nature, this term refers to tiny particles that float in the air. These can be natural, such as dust from sand, sea salt, volcanic ash and sulfates from ocean organisms.
However, many aerosols come from human industry. These include particles created by power plants, vehicle exhaust and ash from wood fires. Although some aerosols are dangerous to breathe, others are harmless. Every kind has a unique effect on the environment.
Because aerosols are so tiny and varied, they’re challenging to study. Researchers rely on equipment like microscopes and spectrometers to understand the composition of these minuscule particles. They then use that data to study their effects on the environment.
The role of aerosols in climate
Once aerosols are expelled into the air, they’re lifted and moved by the wind. Scientists now believe they directly impact weather patterns because of their relationship with heat and humidity. Some aerosols form the nucleus of rain clouds, while others deflect heat from the Earth’s atmosphere.
When certain types of aerosols exist too heavily in the air, they can suppress cloud cover and lead to drought. For example, scientists believe they may have contributed to persistent drought in Africa. However, other aerosols absorb heat and can increase cloud cover and temperature in an area.
Aerosols with cooling effects may actually be serving to reduce the impact of greenhouse gases in the atmosphere. Scientists working on projections about global warming were stumped until they tried adding aerosols to the equation — and then all the numbers made sense.
Aerosols in the Arctic
The role of aerosols in climate change still isn’t fully understood. Their interactions with the environment are complicated and diverse. However, some scientists believe that reducing the number of artificial aerosols in the atmosphere could aggravate the effects of greenhouse gasses.
In the Arctic, warming temperatures are causing changes in climate at a faster rate than most of the planet. Melting ice sheets are adding freshwater to the ocean, affecting currents and changing wildlife habitats.
Researchers studying this area have noticed a strange phenomenon with Arctic aerosols. Instead of following the typical rules for when to transition from a solid to a liquid state, they stay solid at a higher relative humidity than usual. This could affect cloud formation, temperature and weather patterns in the area. Scientists hope to use this information to improve models predicting the effects of climate change.
The impact of aerosols
Warming temperatures and a rise in artificial aerosols have changed global conditions by pushing several planetary boundaries. The solid aerosols discovered in the Arctic may be a response to climate change since they’ve never been observed before.
Regardless of their origin, Arctic aerosols will definitely play a role in the future of climate change. However, researchers are still unsure of what their effects will be. More work is needed to understand how solid aerosols at high humidity levels could impact weather patterns.
Amazingly, artificial aerosols may be working against rising global temperatures by deflecting heat out of the Earth’s atmosphere. More research is needed on the complex relationship between aerosols and the climate before policymakers can decide how to respond.