🌊 Coastal Ocean Methane (CH₄) Analyzer

Complete oceanographic assessment of methane concentration and fluctuation in shallow coastal waters by Claudio Iturra

Real-time analysis of CH₄ distribution, production, consumption, and transport in 100m water column

🌡️ Environmental Parameters

🌊 Physical Oceanography

2°C 15°C 30°C
25 34 PSU 40
1 6 dbar 11
0 0.3 m/s 2
Low 2.0 High
5m 25m 80m

🧪 Chemical Parameters

0 8 mg/L 15
7.0 8.1 8.5
0.5 3 mg/L 20
15 28 mM 35
0 10 μM 50
0 1 μM 5

🦠 Biological Parameters

0.1 5 μg/L 50
10⁵ 5×10⁵ 10⁶
Low 2.0 High
Low 3.0 High

🏖️ Sediment Parameters

0.5% 5% 15%
Low 2.0 High
None 1.0 High

⚡ Quick Scenarios

📊 Methane (CH₄) Analysis & Distribution

🌊 Surface CH₄

0 nM

0% saturation

🌿 Mixed Layer CH₄

0 nM

0 nM/m

🔬 Deep CH₄

0 nM

0x enrichment

💨 Sea-Air Flux

0 μmol/m²/d

Ocean → Atmosphere

⚖️ Net Production

0 nM/d

Production vs Consumption

📈 Fluctuation Index

0

Stability Level

⚗️ Methane Process Rates

Methanogenesis: -- nM/d
Zone: --
Methanotrophy: -- nM/d
Zone: --
Anaerobic Oxidation: -- nM/d
Zone: --
Bubble Transport: -- nM/d
Efficiency: --%

🔄 Methane Sources & Sinks Balance

📈 Sources (Production)
📉 Sinks (Consumption)

🌍 Environmental Controls on CH₄

Temperature Effect: --
Oxygen Control: --
Salinity Impact: --
pH Influence: --
Pressure Effect: --
Mixing Control: --

📈 Depth Profile Analysis

Surface Layer (0-5m)

CH₄: -- nM

Process: --

Flux: -- μmol/m²/d

Mixed Layer

Depth: -- m

CH₄: -- nM

Gradient: -- nM/m

Thermocline

Depth: -- m

CH₄ Change: -- nM

Stability: --

Deep Layer (50-100m)

CH₄: -- nM

Source: --

Transport: --

Benthic Interface

CH₄ Flux: -- nmol/cm²/d

Seepage: --

Oxidation: --%

🧮 Methane Biogeochemical Processes

🦠 Methanogenesis Pathways

Acetoclastic: CH₃COOH → CH₄ + CO₂
Hydrogenotrophic: CO₂ + 4H₂ → CH₄ + 2H₂O
Methylotrophic: CH₃OH → CH₄ + ½O₂

Rate Factors: Temperature (Q₁₀ = 2-4), pH (optimal 6.8-7.2), substrate availability

Inhibitors: O₂, NO₃⁻, SO₄²⁻, high salinity

Depth Distribution: Mainly in anoxic sediments and deep waters

Current Rate: -- nM/d

Dominant Pathway: --

Efficiency: --%

🔥 Methane Oxidation

Aerobic: CH₄ + 2O₂ → CO₂ + 2H₂O
Anaerobic (AOM): CH₄ + SO₄²⁻ → HCO₃⁻ + HS⁻ + H₂O
Nitrite-dependent: CH₄ + 4NO₂⁻ → CO₂ + 2N₂ + 2H₂O

Aerobic Zone: Oxic waters, high efficiency (>95%)

AOM Zone: Sulfate-methane transition zone (SMTZ)

Rate Control: O₂ availability, temperature, microbial biomass

Aerobic Rate: -- nM/d

AOM Rate: -- nM/d

Total Oxidation: -- nM/d

🌊 Physical Transport

Molecular Diffusion: J = -D × (∂C/∂z)
Turbulent Mixing: J = -K_z × (∂C/∂z)
Bubble Transport: J = v_b × C_b × φ

D: Molecular diffusivity (~1.5×10⁻⁹ m²/s at 15°C)

K_z: Vertical eddy diffusivity (10⁻⁶ to 10⁻² m²/s)

Bubble flux: Depends on gas seepage and dissolution

Diffusive Flux: -- nmol/m²/s

Advective Flux: -- nmol/m²/s

Bubble Flux: -- nmol/m²/s

⚗️ Solubility & Partitioning

Henry's Law: C_aq = K_H × P_gas
Temperature: K_H = K_H° × exp(d ln H/d(1/T) × (1/T - 1/T°))
Salinity: K_H = K_H° × exp(k_s × S)

K_H° (25°C): 1.4×10⁻³ mol/L/atm

Salinity effect: k_s = -0.0157 L/mol

Saturation: C_sat = K_H × P_atm × X_CH4

Solubility: -- nM

Saturation Level: --%

Supersaturation: --x

📋 Advanced Methane Analysis

🌊 Biogeochemical Zones

🦠 Microbial Ecology

🌍 Environmental Impact

💡 System Interpretation