Earlier this year the International Panel on Climate Change (IPCC) released a report called AR6 Climate Change 2021 – The Physical Science Basis. The report goes through various changes that have happened, are happening, and are projected to happen to the climate and environment based on a variety of warming scenarios.
The report shows that many of the changes happening such as increased greenhouse gas (GHG) emissions, sea-level rise, warming surface temperatures, increased extreme weather events are all a result of human activity, mainly GHG emissions. The last 50 years have proven to warm and change at rates that haven’t occurred for thousands of years.
The report gives projected scenarios for global temperature increases of 1°C (present warming) 1.5 °C, 2 °C, and 4 °C when compared to the average global temperatures during 1850 – 1900.
Many of the changes occurring are irreversible on the human timescale and will likely take centuries to millennia to revert back to the way they were. Carbon pools such as the land and ocean function at a reduced capacity under higher warming scenarios. The only way to reduce warming and the rate of warming is to reduce GHG emissions. Even if emissions were to completely halt, warming will still occur for years after.
The global water cycle is likely to become more variable under warming conditions, with extremes becoming more severe under higher temperature projections. Precipitation events will become more intense as will droughts. Areas that may experience periods are high precipitation that is then followed by periods of droughts. The extremes will only become more extreme as the world becomes warmer.
The mid-to-high latitudes are expected to experience the greatest rates of warming with an increase in extremely hot days and a decrease in extremely cold days. Although the report focused on a global scale projected scenarios for different locations can be inferred from the information provided. Lake Superior located at mid-latitudes is expected to experience a multitude of changes throughout the rest of the century. Surface temperatures are projected to increase faster than water temperatures, due to the high heat capacity of water. Warmer waters, although nice for swimming can be detrimental to the many cold-thriving species that call Lake Superior home.
Many of the issues that were once thought to be immune to Lake Superior such as algae blooms are already becoming concerns. A warmer future will only exacerbate issues. This summer gave a glimpse into what could become the new normal. Wildfires blazed through many forests in Northwestern Ontario and brought cloudless skies and air quality issues. The drought throughout the summer contributed to the large number of fires burning and also caused concern for agriculture. Forest vegetation also suffered due to the dry conditions and because we live in an interconnected world, the results cascaded throughout the entire ecosystem. Water quality and habitat quality will likely continue to deteriorate under warmer conditions.