User:ATMO629SW/Effects of climate change on humans

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Water

The freshwater resources that humans rely on are highly sensitive to variations in weather and climate. The sustained alteration of climate directly impacts the hydrosphere and hydrologic cycle changing how humans interact with water across the globe. In 2007, the IPCC reported with high confidence that climate change has a net negative impact on water resources and freshwater ecosystems in all regions. The IPCC also found with very high confidence that arid and semi-arid areas are particularly exposed to freshwater impacts. In addition, the IPCC reports increased uncertainty in the amount and frequency of precipitation from the year 2000 to 2100.

As the climate warms, it changes the nature of global rainfall, evaporation, snow, stream flow and other factors that affect water supply and quality. Specific impacts include:

Changes in freshwater availability extend to groundwater as well and human activities in conjunction with climate change interfere with groundwater recharge patterns. One of the leading anthropogenic activities resulting in the depletion of groundwater includes irrigation. Roughly 40% of global irrigation is supported by groundwater and irrigation is the primary activity resulting in groundwater storage loss across the U.S. Furthermore, in the US an estimated 800km^3 of groundwater was depleted in the past century. The development of cities and other areas of highly concentrated water usage has created a strain on groundwater resources. Surface water and groundwater interactions experience reduced "interflow" between the surface and subsurface in post- development scenarios leading to depleted water tables. Groundwater recharge rates are also affected by rising temperatures which increase surface evaporation and transpiration resulting in decreased soil water content. These anthropogenic changes to groundwater storage, such as over pumping and the depletion of water tables, effectively reshape the hydrosphere and impact the ecosystems that depend on the groundwater.
 * Warmer water temperatures affect water quality and accelerate water pollution.
 * Sea level rise is projected to increase salt-water intrusion into groundwater in some regions. This reduces the amount of freshwater available for drinking and farming.
 * In some areas, shrinking glaciers and snow deposits threaten the water supply. Areas that depend on melted water runoff will likely see that runoff depleted, with less flow in the late summer and spring peaks occurring earlier. This can affect the ability to irrigate crops. (This situation is particularly acute for irrigation in South America, for irrigation and drinking supplies in Central Asia, and for hydropower in Norway, the Alps, and the Pacific Northwest of North America.)
 * Increased extreme weather means more water falls on hardened ground unable to absorb it, leading to flash floods instead of a replenishment of soil moisture or groundwater levels.
 * Increased evaporation will reduce the effectiveness of reservoirs.
 * At the same time, human demand for water will grow for the purposes of cooling and hydration.
 * Increased precipitation can lead to changes in water-borne and vector-borne diseases.

Electricity

Climate Change increases the risk of wildfires that can be caused by power lines. In 2019, after a "red flag" warning about the possibility of wildfires was declared in some areas of California, the electricity company "Pacific Gas and Electric (PG&E)" begun to shut down power, for preventing inflammation of trees that touch the electricity lines. The 2019 incident was preceded by the widely documented  "Camp Fire" in Northern California. This 2018 wild fire resulted from the failure to "de-energize" power lines during high wildfire risk times. The New York Times reported 86 deaths and nearly $17 billion in damages from "Camp Fire". As a result, arguably climate change forces public - private partnerships such as PG&E to revaluate insurability and liability for damages from their utilities since climate change has altered the predictability of service delivery in this circumstance.

Increased climactic variability creates a liability burden on the ability of public utilities to perform reliably and how their services are ensured by insurance companies. An example of the issues public utilities face from unexpected climate disasters can be observed in the failure of ERCOT (Electric Reliability Council of Texas) to deliver electricity during unexpected freezing weather in Texas. Electric utilities failing to deliver under rare circumstances poses difficulties for Insurance companies in managing loses. In this case, The Houston Chronicle reported that the insurance company for ERCOT refused to pay damages as it does not view the damages from the freeze as an accident rather a result of mismanagement. The ERCOT and PG&E cases provide evidence of electric utilities facing new challenges as affected by climate change. The climatic conditions that caused these events are expected to become more frequent because of climate change. Related effects such as power outages could become more common and as a result millions of people would be impacted.

Insurance[edit]
The insurance industry is predicated on managing the risks associated with damages to property and since climate change has direct consequences on the safety of society; insurers must adapt to these changes. According to a 2005 report from the Association of British Insurers, limiting carbon emissions could avoid 80% of the projected additional annual cost of tropical cyclones by the 2080s. A June 2004 report by the Association of British Insurers declared "Climate change is not a remote issue for future generations to deal with; it is, in various forms here already, impacting on insurers' businesses now." The report noted that weather-related risks for households and property were already increasing by 2–4% per year due to the changing weather conditions, and claims for storm and flood damages in the UK had doubled to over £6 billion over the period from 1998–2003 compared to the previous five years. The results are rising insurance premiums, and the risk that in some areas flood insurance will become unaffordable for those in the lower income brackets. There is a measured decrease in the capacity of the insurance industry to "absorb weather-related natural disasters" as the ratio of weather related property loss and total property loss has steadily increased since the 1980's.  The total global cost of climate change related natural disasters from 1980 to 2004 was an estimated US$1.4 trillion of which only $340 billion was insured. The roughly $1 trillion in uninsured property loss is damaging to both insurers and customers.

Financial institutions, including the world's two largest insurance companies: Munich Re and Swiss Re, warned in a 2002 study that "the increasing frequency of severe climatic events, coupled with social trends could cost almost 150 billion US$ each year in the next decade." These costs would burden customers, taxpayers, and the insurance industry, with increased costs related to insurance and disaster relief.

In the United States, insurance losses have also greatly increased. It has been shown that a 1% climb in annual precipitation can increase catastrophe loss by as much as 2.8%. Gross increases are mostly attributed to increased population and property values in vulnerable coastal areas; though there was also an increase in frequency of weather-related events like heavy rainfalls since the 1950s.

In March 2019, Munich Re noted that climate change could cause home insurance to become unaffordable for households at or below average incomes.