It is being debated just how great human impact on the environment is. Earth scientists are debating the end of an era, the Holocene, and suggest we are living in a new epoch known as the Anthropocene because human activity is the dominant influence on global climate. On October 8th, 2018, the Intergovernmental Panel on Climate Change (IPCC) released the Special Report on Global Warming, proposing that we must internationally adjust our former global warming limit of 2°C-rise by 2100 to 1.5°C. According to calculations within this report, to reach this goal, carbon emissions must be reduced by at least 45% by 2030 and reaching a net zero by 2050. Accompanying these efforts, methods of removing greenhouse gases from the atmosphere are urged to be researched. Reaching this 1.5°C goal is possible but requires demanding attention and efficient techniques to make it a reality. IPCC report cited over 6,000 studies, with most of the statistics said with high confidence; there is not a lot of wiggle room to dispute what this states
The Earth has several biotic and abiotic cycles that are heavily interdependent on each other. A chemical spill in Minnesota could leach into groundwater that drains into the Mississippi River, and potentially reach the delta in New Orleans. The disruption of just one aspect of Earth’s sensitive natural cycles creates a domino effect.
One abiotic cycle that everyone is a little familiar with is the water cycle. One of the main concerns between the effects of climate change and the water cycle is the formation of acid rain.
Pollution in the atmosphere is increasing both ocean acidification and soil acidification. To get technical, an increase in acidity means an increase in hydrogen ions. Beginning above sea level, atmospheric carbon dioxide reacts with rain to yield acid rain, or carbonic acid.
- Leaches aluminum from soil clay particles and transfers into larger bodies of water
- Removes minerals and nutrients from soil
- Contains nitrogen which has negative effects on ecosystems
- Acidic water can dissolve lead and copper in plumbing pipes & fixtures
The rain will fall directly into oceans and dissolve, or hit soil on land. Let’s talk about what happens with soil, first.
Acid rain lowers the pH of soils, making the environment harsh for plant life. The acidity of soil is important because it determines nutrient uptake for plants. The chemical compounds may still be in the soil, but not in a form plants are able to utilize. Rain naturally leaches calcium from soil over time, which lowers soil pH, however carbonic acid may also react with clays to leach aluminum, which can raise toxicity of the soil as well as any groundwater the leachate may eventually be in contact with. When acid rain evaporates, it may leave atmospheric sulfate and nitrate particles, which are dangerous to breathe in. Soil acidification is also accelerated by mainstream, but unsustainable, agricultural practices such as the use of artificial fertilizers.
^^ Diagram showing nutrient availability for plants in soil with regards to pH
Now, bringing it back, acid rain may fall directly into the ocean. Over the past 300 million years, the ocean’s pH has averaged around 8.2. Today, it’s pH measures at 8.1, and is projected to continue decreasing by 0.3-0.4 units by the end of the 21st century. Ocean acidity is projected to be 100-150% above what it was prior to the Industrial Age. The ocean can react with atmospheric carbon dioxide directly, without the need of already-problematic acid rain, to form carbonic acid and other bicarbonate products. As the ocean forms these inorganic carbonate products, there are less hydrogen ions available in the water, raising the acidity of the ocean. This is a huge concern for organisms with carbonate shells (such as oysters, shrimp, lobster, and many other planktonic organisms), because there is a lack of available carbonate ions for shell-formation. Because this change in the environment is happening so quickly, there is no time to adapt, and alarming rates of these organisms and their sensitive ecosystems, such as coral reefs, are dying off. Oceans absorb about 22 million tons of CO2 daily, which is about one-third of human related CO2 emissions. Disrupting the food chain will eventually catch up to us.