The Philadelphia Experiment:
a Study on the Reign of Violent Rain in the Delaware Valley, Pennsylvania
Climate Change and Extreme Weather Events

by Daniel Brouse

Overview: Philly, the Delaware Valley and the Greater Philadelphia Metropolitan Area

Plymouth Meeting holds a dual significance as both the cradle of democracy and the cradle of climate change. The recent casualties and infrastructure devastation caused by extreme weather occurrences underscore the enduring impact of cultural, economic, and environmental traditions established in Plymouth Meeting centuries ago. This serves as a reminder of the interconnectedness of past actions and present-day consequences, reinforcing the adage that "what goes around comes around." Philly, the Delaware Valley and the Greater Philadelphia Metropolitan Area, are significantly impacted by climate change in various ways:

  1. Increased Frequency and Intensity of Extreme Weather Events: Violent rain. Climate change has led to an increase in the frequency and intensity of extreme weather events such as hurricanes, heavy rainfall, and heatwaves. These events can result in flash flooding, property damage, infrastructure disruptions, and threats to public safety.
  2. .The Social-Ecological Systems: While biogeophysical factors can be studied using math, physics, and historical records, socio-economic systems pose greater challenges due to the unintended consequences of human behavior and inexplicable consumer choices.
  3. Sea Level Rise and Coastal Flooding: Rising sea levels due to climate change pose a threat to coastal communities in the Delaware Valley, including parts of Philadelphia and surrounding areas. Coastal flooding can lead to property damage, erosion of shorelines, and saltwater intrusion into freshwater sources.
  4. Heatwaves and Urban Heat Island Effect: Climate change contributes to more frequent and intense heatwaves, which can exacerbate the urban heat island effect in densely populated areas like Philadelphia. High temperatures increase energy demand for cooling, strain public health systems, and disproportionately impact vulnerable populations such as the elderly and low-income communities.
  5. Impact on Agriculture and Ecosystems: Climate change affects agricultural productivity and ecosystem health in the Delaware Valley region. Changes in temperature and precipitation patterns can disrupt growing seasons, alter crop yields, and affect water availability for irrigation. Additionally, shifts in habitat suitability can impact wildlife populations and biodiversity.
  6. Public Health Risks: Climate change can exacerbate public health risks in the Greater Philadelphia area, including heat-related illnesses, respiratory problems from poor air quality, and the spread of vector-borne diseases. Vulnerable populations, such as children, the elderly, and those with pre-existing health conditions, are particularly at risk.
  7. Infrastructure Vulnerability: Aging infrastructure in the Delaware Valley is vulnerable to the impacts of climate change, including increased flooding, storm surges, and heat-related damage. Addressing these vulnerabilities requires investment in resilient infrastructure and adaptation measures to withstand future climate risks.

Overall, the Delaware Valley and the Greater Philadelphia Metropolitan Area face multifaceted challenges from climate change, underscoring the importance of proactive mitigation and adaptation efforts to build resilience and protect communities, ecosystems, and infrastructure.

The Schuylkill Meets the Delaware

The area where the Schuylkill River meets the Delaware River in Philadelphia is susceptible to saltwater intrusion and tidal flooding due to several factors:
  1. Proximity to the Delaware Bay: Philadelphia is located near the mouth of the Delaware River, which flows into the Delaware Bay and eventually the Atlantic Ocean. As a result, the city is influenced by tidal fluctuations from the ocean, making it susceptible to tidal flooding during high tide events, especially when combined with storm surges.
  2. Low-lying Geography: Parts of Philadelphia, including areas near the confluence of the Schuylkill and Delaware Rivers, are situated in low-lying coastal zones that are prone to flooding. These areas may experience inundation from rising tides, particularly during king tides or extreme weather events such as nor'easters or hurricanes.
  3. Narrowing of Rivers: The confluence of the Schuylkill and Delaware Rivers creates a narrowing of the waterways, which can exacerbate tidal flooding by funneling water and increasing water levels during high tide. This phenomenon is known as a tidal bore, where tidal waters are funneled upstream and cause flooding in areas along the riverbanks.
  4. Urbanization and Impervious Surfaces: Urban development along the riverside, including the construction of buildings, roads, and other impervious surfaces, can exacerbate tidal flooding by reducing natural flood storage areas and increasing runoff during storms. As a result, water from high tides and storm surges may have limited areas to dissipate, leading to more extensive flooding in urbanized areas.
  5. Climate Change: Sea level rise, driven by global warming and the melting of polar ice caps, is contributing to higher baseline water levels in coastal areas, including Philadelphia. This amplifies the effects of tidal fluctuations and increases the frequency and severity of tidal flooding events, posing risks to infrastructure, property, and public safety.
  6. Saltwater Intrusion:
    • Wildlife: Saltwater intrusion can have significant environmental impacts on the Delaware River and its surrounding ecosystems. Increased salinity levels can harm freshwater species adapted to lower salt concentrations, leading to declines in biodiversity and changes in community composition. Saltwater intrusion can also degrade water quality, affect soil fertility, and damage wetland habitats critical for flood control, nutrient cycling, and wildlife habitat.
    • Increased Salinity: The intrusion of saltwater into soil raises its salinity levels, as salt ions (such as sodium and chloride) accumulate. High salinity can inhibit plant growth and reduce crop yields, as many plant species are sensitive to elevated salt levels. Excess salt in the soil can disrupt the osmotic balance within plant roots, making it difficult for them to absorb water and essential nutrients.
    • Soil Structure Degradation: High salinity can cause soil particles to disperse and compact, leading to poor soil structure. Compacted soils have reduced porosity and drainage capacity, which can result in waterlogging and decreased oxygen availability for plant roots. Soil compaction also impedes root penetration and restricts root growth, further limiting plant productivity.
    • Nutrient Imbalance: Saltwater intrusion can alter the balance of essential nutrients in the soil by displacing beneficial ions and disrupting nutrient cycling processes. For example, high levels of sodium in the soil can interfere with the uptake of potassium, calcium, and magnesium by plants, leading to nutrient deficiencies. Imbalances in soil nutrients can impair plant growth, weaken plant defenses against pests and diseases, and reduce crop quality and yield.
    • Toxicity Effects: Some salts present in saltwater, such as sodium chloride, can be toxic to plants when accumulated in high concentrations. Salt toxicity can cause leaf burn, chlorosis (yellowing of leaves), stunted growth, and even plant death. Additionally, salt-tolerant plant species may outcompete native vegetation in saline-affected soils, leading to changes in plant community composition and reduced biodiversity.
    • Soil Remediation Challenges: Once soil becomes saline due to saltwater intrusion, remediation efforts can be challenging and costly. Techniques such as leaching, flushing, and soil amendments may be used to reduce soil salinity, but these methods often require significant water resources and time to be effective. In severe cases, saline-affected soils may need to be replaced or managed for non-agricultural purposes, limiting their potential for agricultural production.
Overall, the confluence of the Schuylkill and Delaware Rivers in Philadelphia is vulnerable to tidal flooding and saltwater intrusion due to its coastal location, low-lying geography, urbanization, and the influence of climate change on sea levels and storm intensity. Efforts to mitigate tidal flooding risks may include coastal defense measures, improved stormwater management, land use planning, and climate adaptation strategies.

The Philadelphia Violent Rain Experiment

The Greater Philadelphia Area serves as our focal point for studying non-coastal violent rain events. Although situated 78 miles from the nearest coast, Philadelphia has experienced a surge in violent rainstorms since 2021, with each episode yielding more precipitation than the typical monthly average. In addition to enduring Nor'easters and tropical storms from the Southeast, Philadelphia is increasingly subjected to deluges originating from the Gulf of Mexico.

Vine Street Expressway Flooded

Hurricane Ida in the summer of 2021 is a good example. Because of the 85 degrees Fahrenheit Gulf of Mexico ocean temperature, Ida rapidly gained strength right before it made landfall jumping from a Category 1 to a Category 4 storm. The warm air allowed more moisture to be carried as rain. The storm was so large that it was able to pick up more moisture from the Atlantic Ocean. After destroying parts of Florida, the ocean moisture was carried inland and dumped over places like Pennsylvania and New York. Ida caused record flood damage in parts of Pennsylvania. The Philadelphia Inquirer reported, "The remnants of Hurricane Ida destroyed or damaged hundreds of homes in Southeastern Pennsylvania and caused more than $100 million in public infrastructure damage across the state." There were more deaths in the Northeastern USA than where the storm made landfall in Louisiana. The New York Times reported, "The remnants of Hurricane Ida caused flash flooding and a number of deaths and disrupted transit across parts of New York and New Jersey. The storm killed at least 43 people in New York, New Jersey, Pennsylvania and Connecticut and left more than 150,000 homes without power." Ida's Philadelphia area destruction included 5 deaths, 7 tornadoes, record flooding, hundreds of water rescues, and "one incredibly soggy mess." The violent rain in Philadelphia was so extreme that the main road across the city from the Delaware River to the Schuylkill River, the Vine Street Expressway, was turned into a canal. "You could've swam from 22nd Street to about 15th Street," said Justin Galbreath, a district maintenance manager at the Pennsylvania Department of Transportation. As climate change intensifies, the frequency of Vine Street becoming a river will likely increase until such time as it becomes permanent.

The train derailment in Plymouth Meeting (July 17, 2023), the eleven vehicles swept away, and the seven people drowned by flood waters in Washington Crossing (July 15, 2023) were caused by a deluge of rain and flash flooding. "In my 44 years, I've never seen anything like it," Upper Makefield Fire Chief Tim Brewer said. "When the water came up, it came up very swiftly. We do not think that anybody drove into it, that they were actively on that road when it happened." CBS news reported, "Over 6 inches of rain in an hour caused the flash flooding according to Brewer. The fire department was dispatched in that area for a lightning strike and just by happenstance they found 11 cars. Eight people were rescued from the cars and two from the creek." In July and December of 2023, extreme rainfall resulted in sinkholes being exposed in the carbonate rock under Route 202 in nearby King of Prussia, PA.

In September of 2023, the Philadelphia Inquirer reported, "The remnants of Tropical Storm Ophelia soaked the entire Philadelphia region with episodic downpours on Saturday, the first day of fall, conspiring to incite 60-mph wind gusts at the Shore and high-tide flooding that closed numerous roads in beach and back-bay towns." There were up to 8 inches of rain recorded throughout the Philadelphia region over the three day event.

The winter of 2023 saw near weekly atmospheric river flash flooding events. On January 9, the Greater Philadelphia Region incurred an historic winter tropical violent rain event. CBS news reported, "If it feels like it's been an abnormally rainy few weeks, you're right. Normal rainfall totals between Dec. 1 and Jan. 9 amount to about 4.78 inches. Between December 2023 and Tuesday, we'd already recorded more than 9 inches of rain, an amount normally recorded in December, January and February combined." The January 9 storm brought over 4 inches of rain to many areas. The Delaware River peaked at its highest level ever. There were hurricane strength winds with wind gusts over 70mph.

On March 23, 2024, Philadelphia witnessed its wettest March day on record. The rain gauge at the airport measured over 3 inches of rainfall, with parts of New Castle County, Delaware, also receiving over 3 inches. Some areas in Gloucester County and Camden County, New Jersey, recorded rainfall exceeding 4 inches. The precipitation observed on that day was roughly equivalent to the typical rainfall for the entire month. A young girl was swept away by the rapidly rising and swift moving waters of the Chester Creek in Delaware County, PA. On the same day, an atmospheric river event brought heavy rains to Brazil's Rio de Janeiro state, resulting in at least nine fatalities, with Petropolis being the hardest hit. A staggering 270 mm (11 inches) of rain fell within 24 hours, significantly impacting the region and leading to numerous incidents, including landslides and house collapses.

Between April 1 and 4, 2024, Southeastern Pennsylvania experienced another severe weather event attributed to atmospheric rivers and strong winds. Rainfall accumulation exceeded 3 inches, accompanied by wind gusts ranging from 35 to 45 mph. Tragically, two individuals lost their lives in unrelated incidents, one in Montgomery County and the other in Delaware County, when trees collapsed onto their vehicles. Blue Marsh State Park had to shut down when the lake unexpectedly rose by nine feet overnight.

Humans are making the Earth hotter. The cool water from the melting ice at the poles is being drawn toward the center of the Earth and getting warmed to record high temperatures. The warm, moist air is circulating and moving over land. The average time moisture stays in the air is 9 days before it turns into precipitation. The warmer the air becomes, the more rain the atmosphere holds and dumps; therefore, violent rain events are increasing in frequency and intensity.

The greatest short term risk to the Earth is violent rain (liquified water vapor). The greatest short term risk to human health is deadly humid heat (hot water vapor).

* Our climate model employs chaos theory to comprehensively consider human impacts and projects a potential global average temperature increase of 9℃ above pre-industrial levels.

What Can I Do?
There are numerous actions you can take to contribute to saving the planet. Each person bears the responsibility to minimize pollution, discontinue the use of fossil fuels, reduce consumption, and foster a culture of love and care. Be a butterfly and affect the world. The Butterfly Effect illustrates that a small change in one area can lead to significant alterations in conditions anywhere on the globe. Hence, the frequently heard statement that a butterfly in China can cause a hurricane in the Atlantic.
Here is a list of additional actions you can take.

The Decline of Penn's Sylvania Brouse (2024)
Hypothesis: Plymouth Meeting is the cradle of climate change. Brouse (2024)
How is All Real Estate at Risk From Climate Change? Brouse and Mukherjee (2024)
Flood Insurance Brouse and Mukherjee (1995-present)

Climate Change: Atmospheric Rivers

Violent Rain and the Substrate

Climate Change, the Jet Stream, and East Coast Atmospheric Rivers

Climate Change: Rate of Acceleration

Climate Change: How Long Is "Ever"?

The Human Induced Climate Change Experiment

The Philadelphia Spirit Experiment Publishing Company
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