Climate Change refers to changes in Earth’s overall weather patterns, including drought, flooding and extreme temperatures. These changes affect people, animals, plants, and the natural environment and they can have far-reaching health impacts on our lives and livelihoods.
Human activities are contributing to climate change by adding heat-trapping greenhouse gases into the atmosphere. These gases are mainly from burning fossil fuels like coal, oil and gas, deforestation, and land-use changes like agriculture. This is in addition to natural processes that also influence the climate, such as cyclical ocean patterns (El Nino and La Nina), volcanic activity, and changes in solar output and the planet’s orbit.
Warmer air can cause more frequent and intense heat waves, which in turn can increase the number of heat-related deaths in the United States. Certain populations — particularly children, pregnant women, the elderly, and those with lower incomes — are at greater risk of these deaths, especially in the summer months.
Changing weather patterns can impact our food supply, with crops and livestock affected by drought or floods. These changes can lead to shortages of some foods and increased prices for others. Many developing countries rely on agriculture as their main source of income, and therefore are at a particular risk from the effects of climate change.
In addition, the changing climate poses a risk to water supplies worldwide, as it can lead to increased water-related diseases such as diarrhea, cholera and other parasites. It can also result in less clean drinking water, as water systems are overwhelmed by heavy rainfall and flooding.
Climate change can also negatively impact biodiversity and ecosystems. In the short term, extreme events like floods and drought can disrupt wildlife habitats. Over the long term, changes in temperature can destroy or alter animal and plant species, including some that are not yet extinct.
Global average near-surface temperature has been steadily increasing since the mid-20th century, mainly as a result of human activities. The last decade was the warmest on record, and the current warming trend is expected to continue.
Limiting climate change to 1.5oC above pre-industrial levels would help avoid the most damaging impacts. However, the risks increase with every additional degree above 1.5oC. This is because some key thresholds may already have been passed – such as for sea ice, glaciers and permafrost.
There is a strong scientific consensus that human activity has been the dominant factor driving climate change. This is because the resulting emissions of carbon dioxide and other greenhouse gases are rapidly increasing atmospheric temperatures. These temperatures are then responding to a complex system of feedbacks and forcing other components of the climate system into unnatural behavior. This includes melting of polar ice sheets, rising sea level, and changes in the frequency and intensity of storms, flooding and droughts. It is important to understand how these different parts of the climate system interact with each other. This understanding helps scientists to create a more accurate picture of how human activities are impacting the Earth’s temperature, and hence climate change.