Acid Rain How does it form? Where is this a problem? What does it do to ecosystems and people?

Acid Deposition formation: Secondary or primary pollutant Acid Deposition formation: Secondary or primary pollutant? Sources for precursors? Transportation? Wet or dry deposition? Practice diagram interpretation. Answer the questions in your quad based on the diagram. Be ready to explain what observation lead you to your inference. Answers: secondary – SOX from source, but “acid rain” from clouds after mixing in air Sources – trucks, factories – arrows point away Yes, transported – arrows suggest transportation Both wet and dry deposition (snow/particles vs. rain)

Formulas you need to memorize: SO3 + H2O = H2SO4 (sulfuric acid) NOx + H2O = 2HNO3 (nitric acid) These are two forms (flavors) of acid deposition. Top is balanced. NOx formula is not balanced because it is a summary equation of many steps that students don’t need to know.

Acid rain < pH 5.6 THIS IS NOT ACID RAIN!!! Normal rain CO2 + H2O  H2CO3 (carbonic acid) Normal rain is always slightly acidic! THIS IS NOT ACID RAIN!!! THIS IS NOT POLLUTION!!!! Acid rain < pH 5.6 All rain is acidic, but not all rain is acid rain.

OBSERVATIONS. IS ACID RAIN A BIG PROBLEM IN HOUSTON OBSERVATIONS? IS ACID RAIN A BIG PROBLEM IN HOUSTON? WHERE IS ACID RAIN A BIG CONCERN?

Global acid rain areas of concern

Add a new page to your flip chart Second page – acid rain Draw the same atmosphere layers, sources, and“talkie bubbles” in blue or black Add precursors for acid rain in the bubbles in RED. Copy the two acid rain equations in the troposphere in RED. Which equation should you NOT add in?

Effects on terrestrial systems: Direct damage to leaves and roots Weak trees are susceptible to insects and disease

Acid deposition leaches nutrients from soil and makes toxins (Al3+) more soluble

Effects on Aquatic ecosystems Loss of biodiversity Range of tolerance Jelly-like fish eggs broken down Acidity denatures enzymes Acid shock – sudden increase in acidity, often in spring can cause fish kills Aluminum ions (Al3+) are released from lake bed, suffocating fish Below pH4.5, lakes devoid of fish

Cultural effects of acid rain Marble and limestone Acid breaks down these basic materials

Many famous buildings are being damaged Taj Mahal Parthenon

Statue of liberty Loss of artistic detail in Acropolis

Human health effects of acid rain Contributes to bronchitis and asthma

Acid Rain: Check your notes! How does it form? Where is this a problem? What does it do to ecosystems (aquatic and terrestrial systems) and people?