There are many worldwide scientific organizations that believe climate change is caused by human action. This is creating an imbalance in Earth’s energy budget. Before the Industrial Revolution, Earth was in radiative balance, with 240 watts per meter-squared (W/m²) hitting the surface of Earth, and 240 W/m² escaping from Earth’s atmosphere. However, it has been estimated that currently there is approximately 0.5 W/m² less energy escaping back into space as a result of human activity (NASA 2021). Despite this being a seemingly small difference, the 0.5 W/m² change is increasing the temperature of Earth’s atmosphere.

As Earth’s atmosphere warms, glacial ice melts, exposing the dark surface of Earth which reduces the albedo, or reflectivity of Earth’s surface. With less reflective material covering Earth, less light gets reflected back into space, and more gets absorbed by Earth’s surface, contributing further to warming. This amplification of warming is known as a positive feedback loop. Rising temperatures are also causing the melting of permafrost, the frozen soil sublayer in the poles. As permafrost melts, bacteria decompose organic matter anaerobically. This produces methane, an even more potent GHG than CO₂. The release of methane increases the concentration of GHGs in the atmosphere and therefore contributes to Earth’s warming temperatures which melts more permafrost, another example of positive feedback. Global sea level has risen by about 8 inches since reliable record keeping began in 1880. It is projected to rise another foot by 2100. This is the result of added water from melting land ice and the expansion of seawater as it warms (NOAA 2022). Warmer water takes up more space than cooler water, causing sea levels to rise. Rising sea levels lead to destruction of land through erosion and flooding. Furthermore, as ocean levels rise, humans are forced to evacuate their communities. These displaced people have come to be known as climate refugees. In addition, as sea levels rise, ocean water is pushed inland against the fresh water of rivers. This phenomenon, known as saltwater intrusion, contaminates drinking water sources of coastal areas, and changes the salinity of estuaries which impacts the structure and function of estuarine ecosystems.

Climate disasters are increasing in number and gravity and are impacting economies around the world. In 2024, there have been 24 weather and climate disaster events with losses exceeding $1 billion each across the United States (NOAA 2024). The rise in temperature has caused plants to migrate from their original habitats to places that are within their preferred temperature range. Climate change is having profound impacts on Earth’s ecosystems, leaving them less resilient and less able to provide the ecosystem services upon which humanity depends. As the effects of climate change continue, the scarcity of resources will increase conflicts among countries and people around the world.

Regionally, the northeastern U.S. will experience more heat waves, heavy downpours and sea level rise. “Infrastructure, agriculture, fisheries and ecosystems will be increasingly compromised” (NASA n.d.). As a result, many states and cities are incorporating climate change into their planning.