Climate Change is the defining issue of our time and we are at a defining moment. From shifting weather patterns that threaten food production to rising sea levels that increase the risk of catastrophic flooding, the impacts of climate change are global in scope and unprecedented in scale. Without drastic action today, adapting to these impacts in the future will be more difficult and costly. The rising average temperature of Earth's climate system, called global warming, is driving changes in rainfall patterns, extreme weather, the arrival of seasons, and more. Collectively, global warming and its effects are known as climate change.
Climate is often defined as the average weather at a particular place, incorporating such features such as temperature, precipitation, humidity, and windiness. A more specific definition would state that climate is the mean state and variability of these features over some extended period. Both definitions acknowledge that the weather is always changing, owing to instabilities in the atmosphere. And as the weather varies from day to day, the climate changes from daily day-and-night cycles up to periods of geologic time hundreds of millions of years long. In a very real sense, climate variation is a redundant expression—the climate is always varying. No two years are exactly alike, nor are any two decades, any two centuries, or any two millennia.
It is much easier to document evidence of climate variability and past climate change than it is to determine their underlying mechanisms. Climate is influenced by a multitude of factors that operate at timescales ranging from hours to hundreds of millions of years.
Causes of Climate Change
Solar Variability
The sun has powered almost everything on Earth since life began, including its climate. The sun also delivers an annual and seasonal impact, changing the character of each hemisphere as Earth's orientation shifts through the year. Over the past century, Earth's average temperature has increased by approximately 0.6 degrees Celsius (1.1 degrees Fahrenheit). Solar heating accounts for about 0.15 C, or 25 percent, of this change, according to computer modeling results published by NASA Goddard Institute for Space Studies researcher David Rind in 2004. Earth's climate depends on the delicate balance between incoming solar radiation, outgoing thermal radiation, and the composition of Earth's atmosphere. Even small changes in these parameters can affect the climate. Around 30 percent of the solar energy that strikes Earth is reflected back into space. Clouds, atmospheric aerosols, snow, ice, sand, ocean surface, and even rooftops play a role in deflecting the incoming rays. The remaining 70 percent of solar energy is absorbed by land, ocean, and the atmosphere.
Volcanic Activity
Volcanic activity can influence the climate in a number of ways at different timescales. Individual volcanic eruptions can release large quantities of sulfur dioxide and other aerosols into the stratosphere, reducing atmospheric transparency and thus the amount of solar radiation reaching Earth’s surface and troposphere.The troposphere is the lowest layer of Earth's atmosphere, and is also where nearly all weather conditions take place. It contains 75% of the atmosphere's mass and 99% of the total mass of water vapour and aerosols. Volcanic activity ranges from the emission of gases, non-explosive lava emissions to extremely violent explosive bursts that may last many hours. A volcanic event occurs when there is a sudden or continuing release of energy caused by near-surface or surface magma movement. A recent example is the 1991 eruption in the Philippines of Mount Pinatubo, which had measurable influences on atmospheric circulation and heat budgets. Volcanoes and related phenomena, such as ocean rifting and subduction, release carbon dioxide into both the oceans and the atmosphere. Emissions are low; even a massive volcanic eruption such as Mount Pinatubo releases only a fraction of the carbon dioxide emitted by fossil-fuel combustion in a year. At geologic timescales,however, the release of this greenhouse gas can have important effects.
Tectonic Activity
Tectonic movements of Earth’s crust have had profound effects on climate at timescales of millions to tens of millions of years. These movements have changed the shape, size, position, and elevation of the continental masses as well as the bathymetry of the oceans. Topographic and bathymetric changes in turn have had strong effects on the circulation of both the atmosphere and the oceans. For example, the uplift of the Tibetan Plateau during the Cenozoic Era affected atmospheric circulation patterns, creating the South Asian monsoon and influencing climate over much of the rest of Asia and neighboring regions. Tectonic activity (earthquakes, volcanoes, and mountain building) is common at plate boundaries, where the edges of two (or more) plates are in contact along huge linear zones of faulting. Plate tectonics is the study of these crustal slabs, and how they interact at their edges.
Greenhouse gases
Greenhouse gases are gas molecules that have the property of absorbing infrared radiation (net heat energy) emitted from Earth’s surface and reradiating it back to Earth’s surface, thus contributing to the phenomenon known as the greenhouse effect. Carbon dioxide, methane, and water vapor are the most important greenhouse gases, and they have a profound effect on the energy budget of the Earth system despite making up only a fraction of all atmospheric gases. Human activities—especially fossil-fuel combustion since the Industrial Revolution—are responsible for steady increases in atmospheric concentrations of various greenhouse gases, especially carbon dioxide, methane, ozone, and chlorofluorocarbons (CFCs).
Effects of climate change
Ice is melting worldwide, especially at the Earth’s poles. This includes mountain glaciers, ice sheets covering West Antarctica and Greenland, and Arctic sea ice. In Montana's Glacier National Park the number of glaciers has declined to fewer than 30 from more than 150 in 1910.
Much of this melting ice contributes to sea-level rise. Global sea levels are rising 0.13 inches (3.2 millimeters) a year, and the rise is occurring at a faster rate in recent years.
Rising temperatures are affecting wildlife and their habitats. Vanishing ice has challenged species such as the Adélie penguin in Antarctica, where some populations on the western peninsula have collapsed by 90 percent or more.
As temperatures change, many species are on the move. Some butterflies, foxes, and alpine plants have migrated farther north or to higher, cooler areas.
Precipitation (rain and snowfall) has increased across the globe. Yet some regions are experiencing more severe drought, increasing the risk of wildfires, lost crops, and drinking water shortages.
Some species—including mosquitoes, ticks, jellyfish, and crop pests—are thriving. Booming populations of bark beetles that feed on spruce and pine trees, for example, have devastated millions of forested acres in the U.S.
Impacts of Climate Change and How to Protect Yourself
Damage to your home
Floods, the most common and deadly natural disasters will likely be exacerbated and intensified by sea-level rise and extreme weather. Heavy precipitation is projected to increase throughout the century to potentially three times the historical average. The frequency and intensity of droughts and wildfires are on the rise. While no state is immune to wildfires, 13 states in the West are considered susceptible to the most severe wildfire damage, with California having the most acres burned in 2018. A national analysis found that 775,654 homes are at extreme risk of wildfire in these 13 states. But even if homes do not burn to the ground, they may suffer smoke and fire damage, as well as water damage and flooding from fire fighting efforts.
How to protect yourself?
Flooding:
Apply sealants and coatings to prevent floodwaters from entering your house
Install a sump pump
Keep your gutters and drains clear
Where flooding occurs regularly, raise your home up on stilts or piles
Wildfires:
Remove dry vegetation around the house
When replacing a roof, opt for tile or metal
Take all evacuation warnings seriously and have an emergency supply kit ready to go
More expensive home insurance
As insurance companies pay out huge amounts to homeowners whose houses have been damaged by climate change impacts, many are raising premiums to offset their costs. Home insurance rates increased by more than 50 percent between 2005 and 2015.
In high-risk areas, premiums and deductibles may rise, coverage may be more limited, and insurance could ultimately become unaffordable or unavailable for some, especially in climate-vulnerable areas.
How to protect yourself
When choosing a home, factor in climate risks
Check FEMA flood maps (even though almost 60 percent are out of date)
Understand your insurance coverage and needs
Shop around for your insurance policy
Raise your deductible for lower monthly payments
Make your home more disaster-resistant
Higher electric bills and more blackouts
As temperatures rise, people will need to stay cool for health and comfort reasons. Climate Central analyzed 244 cities in the U.S. and determined that 93 percent experienced an increase in the number of days that required extra cooling to remain comfortable. As we rely more heavily on air conditioners and fans, electricity bills will get higher.
The increased demand for electricity, especially during peak periods, can also over-tax the electrical grid, triggering brownouts(A brownout is an intentional or unintentional drop in voltage in an electrical power supply system or blackouts). Extreme weather, such as hurricanes, heatwaves, or snowstorms, can cause power outages too.
How to protect yourself
Find greener ways to stay cool
Install a programmable thermostat and set the temperature higher
Run your appliances at night
During a blackout, fill the bathtub so you have water to flush toilets; keep freezers and refrigerators closed
If the power goes out, unplug appliances and electronics to avoid damage from electrical surges
Don’t run generators inside the garage or near open windows, to avoid carbon monoxide poisoning
More allergies and other health risks
Warmer temperatures cause the pollen season to be longer and worsen air quality, both of which can result in more allergy and asthma attacks. Ground-level ozone, a major component of smog, which increases when temperatures warm, can also cause coughing, chest tightness or pain, decrease lung function and worsen asthma and other chronic lung diseases.
In addition, after floods or storms, damp buildings may foster mold growth, which has been linked to allergies and other lung diseases.
How to protect yourself
When pollen counts are high or air quality is bad, stay indoors
During a heatwave, limit outside activity during the hottest hours
Stay hydrated
Use insect repellent
Understand how climate impacts can affect your children and take precautions for them
Poor Water Quality
Intense storms and heavy precipitation can result in the contamination of water resources. In cities, runoff picks up pollutants from the streets and can overflow sewage systems, allowing untreated sewage to enter drinking water supplies.
In rural areas, runoff transports animal waste, pesticides, and chemical fertilizer, and can enter drinking or recreational waters. Polluted drinking water can cause diarrhea, Legionnaires’ disease, and cholera; it can also cause eye, ear, and skin infections. In some low-lying coastal areas, sea-level rise could enable salt water to enter groundwater drinking water supplies.
How to protect yourself
Don’t use water you suspect is contaminated to wash dishes, brush teeth, wash or prepare food, make ice, wash hands or make baby formula
Keep bottled water on hand
Decrease your household water use, especially during droughts
Heed government precautions when drinking water is found to be contaminated and boil your water
As global temperatures continue to rise, climate change will affect our wallets, our health, our safety, and our lives. Many people are already feeling these impacts. And while there are ways to adapt on a personal level, some of these changes are going to become more severe and unavoidable over time. The best way to protect ourselves for the future is to support policies and measures that cut carbon emissions and enhance climate resilience. Climate change is very real and it's time we did something about it.
Written by Prapthi Manjunath from Bangalore, Karnataka
Comments