By heeding the IPCC’s urgent advice to limit warming, we may be able to prevent crossing critical thresholds that could have irreparable repercussions for both people and nature.
But if we continue releasing carbon dioxide at its current pace, the future of climate change could look very different. Warmer temperatures will have different effects in each region; lower- and middle-income countries may be particularly hard hit.
Climate change is already happening.
Rising concentrations of heat-trapping greenhouse gases are warming our planet, altering rainfall patterns, and raising sea levels. Rising temperatures increase the risk of heatwaves, floods, droughts, wildfires and heat waves while making crops less productive – leading to food shortages and placing species further at risk of extinction. Many of these changes have already begun taking effect and are predicted to intensify over time.
But we can avoid some of these impacts by rapidly reducing emissions and slowing warming down. Every fraction of a degree that we delay will reduce human suffering and death while protecting more natural systems on Earth.
Climate change is a complex phenomenon, making its effects impossible to accurately predict. Thankfully, scientists are constantly improving their knowledge of both natural and human factors that impact climate. Working collaboratively, they produce assessments reports to better inform us as to what’s occurring now, what may occur in the future, and what steps can be taken against it.
One key factor is “feedbacks.” These positive or negative feedback loops can accelerate or slow climate change. As the atmosphere warms, more water vapour – another greenhouse gas with short lifetime but nonetheless an amplifier of warming – accumulates. Meanwhile, melting glaciers expose dark ocean surfaces and land surfaces to sunlight which further amplifies warming.
Other essential feedbacks involve the sensitivity of climate systems to natural and human-induced forcings. For instance, some Arctic ecosystems are particularly sensitive to warming; as temperatures rise they could breach critical thresholds that lead to irreversible or catastrophic changes.
These impacts are unevenly distributed around the world. Although developing countries have contributed the least greenhouse gas emissions, they will bear most of the consequences of climate change due to its devastating effects. Poor people often lack financial resources necessary for adaptation and are highly dependent on an intact natural world for survival, putting them at particular risk from extreme weather events and biodiversity loss.
It’s happening now.
Climate change is already having an enormous global impact, from coast erosion due to rising sea levels to polar bears’ exposure to hunger and disease as Arctic ice retreats; droughts threaten food supplies and freshwater supplies; heat waves increase deaths caused by malnutrition, dehydration and heart attacks – as well as deaths caused by coastal erosion due to rising sea levels.
Warmer climates tend to bring with them heavier rainfall and storms. Increased water temperatures make coral reefs vulnerable to bleaching and increase the likelihood of flooding, while decreasing carbon sinks (land and ocean ecosystems) means that more carbon enters into the atmosphere as a result.
Extreme weather events are projected to become increasingly severe around the globe, placing more people at risk from climate-related disasters. Climate change exacerbates existing inequities; poor countries that contributed the least to global warming will likely experience its worst effects and have less access to resources for adaptation.
It is likely that the next few years will be among the warmest on record, driven by heat-trapping greenhouse gases and natural factors like an El Nino event. There is currently a 66% probability that near-surface global temperature will surpass 1998 record high temperatures by the end of 2018.
As long as our emissions continue on their current course, it’s impossible for us to avoid passing key thresholds that would lead to irreversible climate change. These critical thresholds, or “tipping points”, would trigger domino effects across Earth’s climate system and accelerate and intensify any initial warming; such examples include Greenland Ice Sheet collapse or rapid thaw of Arctic permafrost that releases carbon dioxide into the atmosphere.
But if we act now, we can reduce emissions and keep global temperatures from increasing by more than 2 degrees Celsius above pre-industrial levels. That is the goal of the Paris Agreement and requires unprecedented global cooperation and action by governments, cities, companies and individuals alike. Progress has already begun: states across the US are supporting renewable energy; mayors and city leaders have prioritized equity when developing climate action plans; while companies have pledged to reach net zero carbon by 2050.
It’s happening in the future.
Many changes already underway are projected to accelerate over the coming decades. We face record-shattering heat waves in California as well as devastating floods and droughts in Africa and Asia that threaten our livelihoods, which could worsen without significant reductions of heat-trapping greenhouse gases emissions.
By cutting fossil fuel use in half by 2030 and eliminating carbon emissions entirely by the early 2050s, our world could still have a chance at keeping warming to 1.5 degrees Celsius above preindustrial levels. Any delay will drastically diminish those odds and guarantee an ever more dangerous future for humanity.
Scientists are witnessing unprecedented climate change worldwide and across Earth’s systems. Some changes such as continued sea level rise may become irreversible over hundreds or even thousands of years.
Although climate pollution will have far-reaching impacts, human ingenuity and people’s shared desire to live on a cleaner world will enable us to reach net zero emissions by 2040. States, cities and corporations alike are advocating renewable energy; prioritizing climate equity policymaking; and pledge to reach net-zero emissions before 2040.
Tackling global climate change will be no easy feat. To be successful in doing so, success must also include addressing intersecting crises of poverty, inequality and climate-related disasters that drive displacement – especially since climate-related impacts will disproportionately affect communities with limited resources.
An important consideration when it comes to wildlife is how climate change will impact their lives. With temperatures shifting, many species will seek cooler environments or higher altitudes as temperatures change, or alter seasonal behavior altogether – creating massive shifts that alter ecosystems fundamentally or result in the extinction of many species.
Coral reefs and Arctic sea ice will likely disappear completely under a 2-degree Celsius warming scenario, while beyond this threshold millions more will continue to experience life-threatening heat waves, water scarcity and coastal flooding.
It’s a matter of time.
The global climate system is an intricate network, and each element will take time to react to atmospheric changes. Response times will differ; for instance, atmosphere and upper layer ocean currents may adapt more quickly than deeper ocean or polar ice sheets.
A doubling of CO2 emissions would result in global warming of about one degree Celsius, but its overall effect will likely be much greater due to feedback processes within the climate system which dampen or amp up initial warming effects. Scientists predict that different parts of the world may respond to climate change at differing rates, creating disparate environmental impacts across global regions.
Humanity’s future hinges upon our ability to effectively address the climate crisis. By mitigating global warming and slowing its impacts, fewer people will be exposed to its impacts, while our civilization can move toward renewable energy sources more quickly. But accomplishing this requires more than human ingenuity; it also necessitates dramatic and rapid reductions of economic, social, and political factors that exacerbate its effects.
Climate Change impacts can already be observed through increased sea level rise, reduced Arctic snow cover, hotter temperatures, severe droughts and wildfires occurring more often, as well as more intense heat waves – many occurring more rapidly than anticipated by scientists.
Climate change has devastating impacts on our natural environment, endangering species globally and placing at risk more than half of all animal species on Earth – from iconic icons like Polar bears and Amazon rainforest inhabitants, such as iconic icons such as Polar bears or iconic creatures like beetles and coral reefs, through to less well-known creatures like beetles and coral reefs. Climate change also exacerbates biodiversity loss through direct exploitation (hunting/poaching) as well as indirect degradation (land conversion to agriculture).
In order to protect biodiversity, comprehensive climate solutions that include strategies that reduce other threats-such as poverty and inequality-are key. Furthermore, to avoid catastrophic levels of warming by 2050 it will be vitally important that greenhouse gas emissions like carbon dioxide are brought down significantly through reductions in coal, oil, and gas usage, plus an unprecedented effort by governments, businesses and individuals alike.
