(CNN) As wildfires ravaged California this year, thousands of firefighters have taken on the massive task of containing and extinguishing flames over hundreds of thousands of acres.

But it's not as simple as showing up and spraying water.

"We don't just put blue stuff on the red stuff," said Scott McLean, spokesman for the California Department of Fire and Forestry Protection, known as Cal Fire.

Wildfires constantly evolve based on weather conditions. That forces firefighters and their incident commanders to constantly re-evaluate their approaches and strategies, including where to position people, equipment and logistical support.

Here's a look at the tactics and tools used by the men and women battling the flames:

Firefighters take to the ground ...

Ground crews maintain the front lines, supported by fire engines carrying hundreds of gallons of water, said Mike Lopez, a 20-year veteran firefighter who is now president of Cal Fire's firefighter union.

These crews are central to the overarching mission: putting out the fire.

Then, there's a simultaneous effort to contain the fire and keep it from spreading. That task falls to hand crews.

A firefighter cuts brush at the Thomas Fire on December 7, 2017, near Fillmore, California.

These firefighters use chainsaws and Pulaskis -- axes used to cut vegetation -- to clear brush that could fuel the fire, McLean said.

The result is what's known as a "fire line." The barrier separates the wildfires and the land that, so far, has been spared, and it slows down the fire's growth.

Hand crews also use bulldozers to do the job on a larger scale.

"But a bulldozer can't go places that a hand crew can go," Lopez said. "They work in tandem."

... and to the air.

Meantime, air crews take on the fire from the sky.

CalFire strategically places aircraft throughout California to ensure a 20-minute response time to any wildfire incident, McLean said.

Among the fleet are helicopters and air tankers -- huge planes fitted with tanks -- that can drop water or fire retardant on blazes , he said.

A helicopter makes a water drop over the Creek Fire on December 5, 2017, in Los Angeles.

Some helicopters get equipped with big buckets to douse fires, Lopez said. They can carry 300 to 800 gallons of water from nearby sources, including lakes, pools, ponds or oceans.

The tactic might seem fail-proof. It's not.

"People think that air tankers and helicopters completely extinguish fires," Lopez said. "They don't. They slow the progression of the fire for the ground resources to put the fire out."

So, the cooperation of firefighters on the ground and those in the sky is critical.

"It's an orchestra," McLean said. "All those components come together."

They try to stay a step ahead of the fire ...

Weather forecasting also plays a central role, Lopez said.

"We watch the weather religiously ... so we can adapt and plan accordingly," McLean told CNN, adding that each firefighter must be aware of weather conditions.

Forecasters look at temperature, relative humidity and wind to assess the possibility or likely intensity of a fire, said Mike Flannigan, a professor of wildland fire at the University of Alberta.

"Wind is the most critical factor once the fire is up and running," he said. "How strong it is, and if it's shifting."

Using forecasts and fire growth models, fire management agencies move crews and resources to where they expect the fire to go.

Based on the models, officials sometimes opt to let the blazes burn, sparing resources and firefighters and letting fires "play a more natural role" in the nature, Flannigan said.

Fire incident commanders get frequent updates from meteorologists and other experts, then share intel with personnel in the field, Lopez said, "so everyone's on the same page."

... and stay long after it goes out.

And the job's not over when the fire's out.

As soon as a fire has been extinguished and firefighters leave, damage assessment teams take stock of the devastation "and document what structures were lost," McLean said. These teams relay information about how many homes and buildings were destroyed.

Photos: Wildfires spread in Southern California Flames from a back-firing operation rise behind a home off Ladera Lane near Bella Vista Drive in Santa Barbara, California, on Thursday, December 14. Powerful Santa Ana winds and extremely dry conditions are fueling wildfires in Southern California in what has been a devastating year for such natural disasters in the state. Hide Caption 1 of 37 Photos: Wildfires spread in Southern California Fire, smoke and ash from the Thomas Fire blanket Santa Barbara on Wednesday, December 13. Hide Caption 2 of 37 Photos: Wildfires spread in Southern California A smoke-filled sky filters sunlight to orange around a surfer as the Thomas Fire continues to grow and threaten communities from Carpinteria to Santa Barbara on Tuesday, December 12, in Carpinteria, California. Hide Caption 3 of 37 Photos: Wildfires spread in Southern California People watch as firefighters battle flames in Carpinteria, California, on Monday, December 11. Hide Caption 4 of 37 Photos: Wildfires spread in Southern California As smoke obscures the sun, a Coulson C-130 air tanker turns to make a drop on a Carpinteria hillside on December 11. Hide Caption 5 of 37 Photos: Wildfires spread in Southern California As the Thomas Fire burns in the background, Dan Bellaart and his wife, Mary McEwen, comfort each other in their backyard in Montecito, California, on December 11. Hide Caption 6 of 37 Photos: Wildfires spread in Southern California The Thomas Fire burns in the mountains near Carpinteria on Sunday, December 10. Hide Caption 7 of 37 Photos: Wildfires spread in Southern California Firefighters battle a wildfire as it advances on homes in Carpinteria on December 10. Hide Caption 8 of 37 Photos: Wildfires spread in Southern California A cloud of smoke overshadows downtown Ventura, California, on December 10. Hide Caption 9 of 37 Photos: Wildfires spread in Southern California Horses are evacuated from the Laughing Dog Ranch as smoke from the Thomas Fire descends on the area in Ojai, California, on Saturday, December 9. Hide Caption 10 of 37 Photos: Wildfires spread in Southern California The shell of a burnt-out bus is seen after fire swept through residential neighborhoods near Ojai on Friday, December 8. Hide Caption 11 of 37 Photos: Wildfires spread in Southern California Flames rise as a fire approaches the Lake Casitas area of Ojai on December 8. Hide Caption 12 of 37 Photos: Wildfires spread in Southern California A burnt Mercedes is seen after the Skirball Fire swept through the Los Angeles neighborhood of Bel-Air on Thursday, December 7. Hide Caption 13 of 37 Photos: Wildfires spread in Southern California Palm trees sway in a gust of wind as a firefighter carries a hose in Ventura on December 7. Hide Caption 14 of 37 Photos: Wildfires spread in Southern California Residents watch the Thomas Fire burn a hillside above La Conchita, California, on December 7. Hide Caption 15 of 37 Photos: Wildfires spread in Southern California Fires surround a hilltop mansion in Los Angeles on Wednesday, December 6. Hide Caption 16 of 37 Photos: Wildfires spread in Southern California "Daddy, the home is gone," Amanda Lewis tells her family on December 6. The Thomas Fire raged through her parents' foothill neighborhood in Ventura. Hide Caption 17 of 37 Photos: Wildfires spread in Southern California Smoke rises across Southern California in this image taken from the International Space Station on December 6. Hide Caption 18 of 37 Photos: Wildfires spread in Southern California A Los Angeles County Fire Department helicopter makes a water drop on flames after the Skirball Fire swept through Bel-Air on December 6. Hide Caption 19 of 37 Photos: Wildfires spread in Southern California Flames from the Thomas Fire burn above a truck north of Ventura on December 6. Hide Caption 20 of 37 Photos: Wildfires spread in Southern California Joyce George, right, comforts neighbor Dawn Reily on December 6. Reily's Ventura home was destroyed by fire. Hide Caption 21 of 37 Photos: Wildfires spread in Southern California Flames consume vehicles in Ventura on Tuesday, December 5. Hide Caption 22 of 37 Photos: Wildfires spread in Southern California Smoke billows from a burning house in Los Angeles as the Creek Fire moves through the area on December 5. Hide Caption 23 of 37 Photos: Wildfires spread in Southern California A man watches as a wildfire burns in Ventura on December 5. Hide Caption 24 of 37 Photos: Wildfires spread in Southern California The Creek Fire burns on a hillside in the Shadow Hills neighborhood of Los Angeles on December 5. Hide Caption 25 of 37 Photos: Wildfires spread in Southern California A firefighter battles a blaze in the Lake View Terrace area of Los Angeles on December 5. Hide Caption 26 of 37 Photos: Wildfires spread in Southern California Antoine Hanna comforts his wife, Tammy, after firefighters saved their home in Ventura on December 5. Hide Caption 27 of 37 Photos: Wildfires spread in Southern California This Ventura apartment complex, seen on December 5, was destroyed by fire. Hide Caption 28 of 37 Photos: Wildfires spread in Southern California A firefighter sprays water at a burning house in the Lake View Terrace area of Los Angeles on December 5. Hide Caption 29 of 37 Photos: Wildfires spread in Southern California Palm trees burn in Ventura on December 5. Hide Caption 30 of 37 Photos: Wildfires spread in Southern California Ventura County firefighter Aaron Cohen rests on December 5. Hide Caption 31 of 37 Photos: Wildfires spread in Southern California A man prepares to evacuate his house in Santa Paula, California, on December 5. Hide Caption 32 of 37 Photos: Wildfires spread in Southern California A man tries to catch a horse that got loose in the Lake View Terrace area of Los Angeles on December 5. Hide Caption 33 of 37 Photos: Wildfires spread in Southern California Shrubs burn near a home in Ventura on December 5. Hide Caption 34 of 37 Photos: Wildfires spread in Southern California James and Josie Ralstin carry belongings retrieved from their home in Ventura on December 5. Hide Caption 35 of 37 Photos: Wildfires spread in Southern California Firefighters work to put out a blaze engulfing homes in Ventura on December 5. Hide Caption 36 of 37 Photos: Wildfires spread in Southern California The Thomas Fire burns along a hillside near Santa Paula on December 5. Hide Caption 37 of 37

Behind those teams come other experts who assess and repair damage the fire may have caused to the watershed, which could lead to long-term erosion problems, McLean said.

With wildfire seasons predicted to get longer, the strategies -- from the front lines to the repair work -- undoubtedly will be required more often. And incident commanders, firefighters and others will be there, McLean said, "however long it takes to get done."