Initial Abstraction 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%
✖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%
✖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%

✖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 [I_a]

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Initial Abstraction Solution

STEP 0: Pre-Calculation Summary

Formula Used

Initial Abstraction = Total Precipitation-Cumulative Infiltration-Direct Surface Runoff
I_a = P_T-F-Q
This formula uses 4 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.
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.
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.

STEP 1: Convert Input(s) to Base Unit

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

STEP 2: Evaluate Formula

Substituting Input Values in Formula

I_a = P_T-F-Q --> 16-2-9

Evaluating ... ...

I_a = 5

STEP 3: Convert Result to Output's Unit

5 Cubic Meter --> No Conversion Required

FINAL ANSWER

5 Cubic Meter <-- Initial Abstraction

(Calculation completed in 00.004 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 Formula

LaTeX Go

Initial Abstraction = Total Precipitation-Cumulative Infiltration-Direct Surface Runoff
I_a = P_T-F-Q

What is Water Balance Model?

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.

What is Initial Abstraction?

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?

Initial Abstraction calculator uses Initial Abstraction = Total Precipitation-Cumulative Infiltration-Direct Surface Runoff to calculate the Initial Abstraction, The Initial Abstraction formula is defined as the parameter that accounts for all losses prior to runoff and consists mainly of interception, infiltration, evaporation, and surface depression storage. Initial Abstraction is denoted by I_a symbol.

How to calculate Initial Abstraction using this online calculator? To use this online calculator for Initial Abstraction, enter Total Precipitation (P_T), Cumulative Infiltration (F) & Direct Surface Runoff (Q) and hit the calculate button. Here is how the Initial Abstraction calculation can be explained with given input values -> 5 = 16-2-9.

FAQ

What is Initial Abstraction?

The Initial Abstraction formula is defined as the parameter that accounts for all losses prior to runoff and consists mainly of interception, infiltration, evaporation, and surface depression storage and is represented as I_a = P_T-F-Q or Initial Abstraction = Total Precipitation-Cumulative Infiltration-Direct Surface Runoff. Total Precipitation is the sum of rainfall and the assumed water equivalent of snowfall for a given year, 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 & 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.

How to calculate Initial Abstraction?

The Initial Abstraction formula is defined as the parameter that accounts for all losses prior to runoff and consists mainly of interception, infiltration, evaporation, and surface depression storage is calculated using Initial Abstraction = Total Precipitation-Cumulative Infiltration-Direct Surface Runoff. To calculate Initial Abstraction, you need Total Precipitation (P_T), Cumulative Infiltration (F) & Direct Surface Runoff (Q). With our tool, you need to enter the respective value for Total Precipitation, Cumulative Infiltration & Direct Surface Runoff 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, Cumulative Infiltration & Direct Surface Runoff. We can use 2 other way(s) to calculate the same, which is/are as follows -

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

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