Initial Abstraction given Ratio of Infiltration to Retention Calculator

✖Total Precipitation is the sum of rainfall and the assumed water equivalent of snowfall for a given year.ⓘ Total Precipitation [P_T]			+10% -10%
✖Direct Surface Runoff is the rain or meltwater that runs off during the rain or melt event as overland flow or in the vegetation cover above frozen soil.ⓘ Direct Surface Runoff [Q]			+10% -10%
✖The potential maximum retention mainly represents infiltration occurring after runoff has started.ⓘ Potential Maximum Retention [S]			+10% -10%
✖The cumulative infiltration excluding initial abstraction is total amount of water that soil strata are able to absorb from rainfall or irrigation in a given time.ⓘ Cumulative Infiltration [F]			+10% -10%

✖Initial Abstraction is a parameter that accounts for all losses prior to runoff and consists mainly of interception, infiltration, evaporation, and surface depression storage.ⓘ Initial Abstraction given Ratio of Infiltration to Retention [I_a]

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Initial Abstraction given Ratio of Infiltration to Retention Solution

STEP 0: Pre-Calculation Summary

Formula Used

Initial Abstraction = Total Precipitation-(Direct Surface Runoff*Potential Maximum Retention/Cumulative Infiltration)
I_a = P_T-(Q*S/F)
This formula uses 5 Variables

Variables Used

Initial Abstraction - (Measured in Cubic Meter) - Initial Abstraction is a parameter that accounts for all losses prior to runoff and consists mainly of interception, infiltration, evaporation, and surface depression storage.
Total Precipitation - (Measured in Cubic Meter) - Total Precipitation is the sum of rainfall and the assumed water equivalent of snowfall for a given year.
Direct Surface Runoff - (Measured in Cubic Meter) - Direct Surface Runoff is the rain or meltwater that runs off during the rain or melt event as overland flow or in the vegetation cover above frozen soil.
Potential Maximum Retention - (Measured in Cubic Meter) - The potential maximum retention mainly represents infiltration occurring after runoff has started.
Cumulative Infiltration - (Measured in Cubic Meter) - The cumulative infiltration excluding initial abstraction is total amount of water that soil strata are able to absorb from rainfall or irrigation in a given time.

STEP 1: Convert Input(s) to Base Unit

Total Precipitation: 16 Cubic Meter --> 16 Cubic Meter No Conversion Required
Direct Surface Runoff: 9 Cubic Meter --> 9 Cubic Meter No Conversion Required
Potential Maximum Retention: 2.5 Cubic Meter --> 2.5 Cubic Meter No Conversion Required
Cumulative Infiltration: 2 Cubic Meter --> 2 Cubic Meter No Conversion Required

STEP 2: Evaluate Formula

Substituting Input Values in Formula

I_a = P_T-(Q*S/F) --> 16-(9*2.5/2)

Evaluating ... ...

I_a = 4.75

STEP 3: Convert Result to Output's Unit

4.75 Cubic Meter --> No Conversion Required

FINAL ANSWER

4.75 Cubic Meter <-- Initial Abstraction

(Calculation completed in 00.036 seconds)

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< Basic Theory Calculators

Actual Infiltration

LaTeX Go Cumulative Infiltration = Potential Maximum Retention*(Direct Surface Runoff/(Total Precipitation-Initial Abstraction))

Cumulative Infiltration given Total Precipitation

LaTeX Go Cumulative Infiltration = Total Precipitation-Initial Abstraction-Direct Surface Runoff

Water Balance Equation for Rainfall

LaTeX Go Total Precipitation = Initial Abstraction+Cumulative Infiltration+Direct Surface Runoff

Initial Abstraction

LaTeX Go Initial Abstraction = Total Precipitation-Cumulative Infiltration-Direct Surface Runoff

Initial Abstraction given Ratio of Infiltration to Retention Formula

LaTeX Go

Initial Abstraction = Total Precipitation-(Direct Surface Runoff*Potential Maximum Retention/Cumulative Infiltration)
I_a = P_T-(Q*S/F)

What is Runoff Curve Number?

The Runoff curve number is an empirical parameter used in hydrology for predicting direct runoff or infiltration from rainfall excess. The curve number is based on the area's hydrologic soil group, land use , treatment and hydrologic condition.

What is Water Balance Model & What is Initial Abstraction?

Water Balance Model is a conceptual representation of the hydrologic cycle typically used to apply water balance principles at atmospheric, surface, soil water media, and subsurface scales.
Initial Abstraction is a parameter that accounts for all losses prior to runoff and consists mainly of interception, infiltration, evaporation, and surface depression storage.

How to Calculate Initial Abstraction given Ratio of Infiltration to Retention?

Initial Abstraction given Ratio of Infiltration to Retention calculator uses Initial Abstraction = Total Precipitation-(Direct Surface Runoff*Potential Maximum Retention/Cumulative Infiltration) to calculate the Initial Abstraction, The Initial Abstraction given Ratio of Infiltration to Retention formula is defined as the runoff potential of a soil-cover complex during periods when the soil is not frozen. Initial Abstraction is denoted by I_a symbol.

How to calculate Initial Abstraction given Ratio of Infiltration to Retention using this online calculator? To use this online calculator for Initial Abstraction given Ratio of Infiltration to Retention, enter Total Precipitation (P_T), Direct Surface Runoff (Q), Potential Maximum Retention (S) & Cumulative Infiltration (F) and hit the calculate button. Here is how the Initial Abstraction given Ratio of Infiltration to Retention calculation can be explained with given input values -> 4.75 = 16-(9*2.5/2).

FAQ

What is Initial Abstraction given Ratio of Infiltration to Retention?

The Initial Abstraction given Ratio of Infiltration to Retention formula is defined as the runoff potential of a soil-cover complex during periods when the soil is not frozen and is represented as I_a = P_T-(Q*S/F) or Initial Abstraction = Total Precipitation-(Direct Surface Runoff*Potential Maximum Retention/Cumulative Infiltration). Total Precipitation is the sum of rainfall and the assumed water equivalent of snowfall for a given year, Direct Surface Runoff is the rain or meltwater that runs off during the rain or melt event as overland flow or in the vegetation cover above frozen soil, The potential maximum retention mainly represents infiltration occurring after runoff has started & The cumulative infiltration excluding initial abstraction is total amount of water that soil strata are able to absorb from rainfall or irrigation in a given time.

How to calculate Initial Abstraction given Ratio of Infiltration to Retention?

The Initial Abstraction given Ratio of Infiltration to Retention formula is defined as the runoff potential of a soil-cover complex during periods when the soil is not frozen is calculated using Initial Abstraction = Total Precipitation-(Direct Surface Runoff*Potential Maximum Retention/Cumulative Infiltration). To calculate Initial Abstraction given Ratio of Infiltration to Retention, you need Total Precipitation (P_T), Direct Surface Runoff (Q), Potential Maximum Retention (S) & Cumulative Infiltration (F). With our tool, you need to enter the respective value for Total Precipitation, Direct Surface Runoff, Potential Maximum Retention & Cumulative Infiltration and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well.

How many ways are there to calculate Initial Abstraction?

In this formula, Initial Abstraction uses Total Precipitation, Direct Surface Runoff, Potential Maximum Retention & Cumulative Infiltration. We can use 2 other way(s) to calculate the same, which is/are as follows -

Initial Abstraction = Total Precipitation-Cumulative Infiltration-Direct Surface Runoff
Initial Abstraction = Total Precipitation-Maximum Potential Runoff

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