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6.10 Latitude & Longitude

Latitude and longitude are measuring lines used for locating places on the surface of the Earth. They are angular measurements, expressed as degrees of a circle. A full circle contains 360°. Each degree can be divided into 60 minutes, and each minute is divided into 60 seconds. The symbol for minutes is (´) and for seconds is ("). 

Latitude lines (called parallels) circle the planet's surface in lines parallel to the equator, which lies halfway between the North and South poles. Latitude lines circle the planet from east and west, beginning at 0° at the equator and increasing to 90°North or 90°South.

Longitude lines (called meridians) run north and south and circle the planet from pole to pole. Each line is identified by the number of degrees east or west from a starting point at Greenwich, England, known as the prime meridian. The longitude at the prime meridian is 0°. Longitudes lines mark the distance westward, to 180°West, and eastward, to 180°East.

Earth with Latitude and Longitude

Latitude and longitude measurements can be written in several ways. For example, 211 degrees, 22 minutes, and 30 seconds is written as 211° 22´30", or with spaces: 211 22 30; or with a decimal after the degrees 211.22´30", or with a decimal after the minutes 211 22.30. One degree of latitude equals about 69 miles. One minute is just over a mile, and one second is about 100 feet. 

When adding or subtracting degrees, convert to minutes and seconds as necessary and borrow the appropriate amount (see Section 1.3). For example, when borrowing 1 degree from 360°, change to 359°60´. To borrow 1 minute from 359° 60´, change to 359° 59´60".

Example 1 320°25´32" - 210°50´41" 

degrees min seconds

Step1. Subtract 1 from 2.
2 - 1 = 1

Step 2. Borrow 1 minute from the 5 for the seconds.
There are 60 seconds in 1 minute.
60 + 30 = 90

Step 3. Subtract 4 from 9.
9 - 4 = 5

Step 4. Subtract 0 from 4.
4 - 0 = 4

Step 5. Borrow 1 degree from 20° for the minutes. There are 60 minutes in 1 degree.
60 + 20 = 80

Step 6. Subtract 5 from 8.
8 - 5 = 3

Step 7. Subtract 210 from 319.
319 - 210 = 109

109°34´51"
 

Example 2 - Add 142° 54´ 43" + 85° 36´ 44".
 
degrees min seconds

Step 1. Add the seconds. 43 + 44 = 87
Sixty seconds equals 1 minute.

Step 2. 87 is greater than 60, so subtract 60 seconds from 87 seconds. There are 60 seconds in 1 minute, so add 1 minute to the minute column.
87 - 60 = 27 seconds

Step 3. Add the minutes.
54 + 36 + 1 (carried over from the seconds) = 91 minutes

Step 4. 91 is greater than 60, so subtract 60 minutes from 91 minutes. There 60 minutes in 1 degree, so add 1 to the degree column. 91 - 60 = 31 minutes

Step 5. Add the degrees.
142 + 85 + 1 (carried over from the minutes) = 228 degrees

228°31´27"

Example 3 - Name the range of latitude and longitude for the borders of Wyoming.

Step 1. Find Wyoming on a map.

Step 2. Locate the east and west borders of Wyoming. 

Longitude 111°W to 104°W. It is west of the Greenwich Longitude.

Step 3. Find the north and south borders of Wyoming.

Latitude 41°N to 45°N. The location is north of the equator.

NWCG Latest Announcements

NEW! S-290, Intermediate Wildland Fire Behavior (Blended) Available Now

Date: Aug 15, 2025
Questions? Please contact:
Fire Behavior Subcommittee

NWCG is excited to announce that the S-290, Intermediate Wildland Fire Behavior (Blended) training is now available on the Wildland Fire Learning Portal. S-290 (Blended) training combines online training and instructor-led training components that support individuals working towards any Single Resource Boss or Fire Effects Monitor incident qualifications.

This second course in the series collectively serves to develop fire behavior prediction knowledge and skills, and provides more detailed information on fuels, weather, and topography that affect wildland fire behavior for safety purposes.

Students are required to finish the prerequisite S-190, Introduction to Wildland Fire Behavior, before enrolling in S-290, Intermediate Wildland Fire Behavior (Blended).

References:

S-290, Intermediate Wildland Fire Behavior (Blended)

S-190, Introduction to Wildland Fire Behavior

Wildland Fire Learning Portal

NEW! S-271, Helicopter Crewmember (Blended) Now Available

Date: Aug 14, 2025
Questions? Please contact:
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The S-271, Helicopter Crewmember (Blended) is now available. Developed through the Incident Performance and Training Modernization (IPTM) effort, this training supports individuals working towards Helicopter Crewmember (HECM) incident qualifications. 

S-271, Helicopter Crewmember (Blended) training combines online training and instructor-led training components. This course is designed to provide students with the knowledge and skills necessary to perform the duties of the HECM position, as described in the NWCG Incident Position Standards for Helicopter Crewmember, PMS 350-22.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1, scheduled for January 2026.

References:

S-271, Helicopter Crewmember (Blended)

NWCG Helicopter Crewmember (HECM) Position Page

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Incident Position Standards and Next Generation Position Task Books Now Available for FBAN and LTAN

Date: Aug 13, 2025
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NWCG is excited to announce that Incident Position Standards and Next Generation Position Task Books are now available for Fire Behavior Analyst (FBAN) and Long Term Fire Analyst (LTAN).

The Performance Support Packages for these positions were developed as part of the Incident Performance and Training Modernization (IPTM) effort. These resources support trainees, qualified personnel, and evaluators in their respective roles.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1, scheduled for January 2026.

References:

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ETC/RMC Safety Bulletin: 25-001 New Guidance on Laundering Wildland Fire Clothing to Reduce Contamination

Date: Aug 8, 2025
Questions? Please contact:
Equipment Technology Committee
 Risk Management Committee

The Equipment Technology Committee (ETC) and the Risk Management Committee (RMC) have issued Safety Bulletin 25-001: Laundering to Decontaminate Wildland Fire Clothing. Recent research revealed that wildland fire flame-resistant pants and shirts can be contaminated with chemicals from combustion byproducts, including carcinogens, and that common laundering practices can effectively remove these harmful contaminants from wildland firefighter clothing more effectively than previously understood. It is recommended to decontaminate wildland fire clothing as frequently as possible. 

Frequently Asked Questions about this new information and how to implement recommendations can be found on the NWCG Alerts page. Read the complete ETC/RMC Safety Bulletin: 25-001 to learn more. 

References:

NWCG Alerts

ETC Safety Bulletin: 25-001

Frequently Asked Questions (FAQ) on Laundering to Decontaminate Wildland Fire Clothing

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