Mammoth Upper Terraces–What a Difference a Day Makes

A winter morning on Mammoth Hot Springs’ Upper Terraces. Wow, what a difference a day hour makes! From blue skies to whiteout snow conditions in a matter of hours, but I always love the peace and beauty when walking the Upper Terraces. Let’s explore these amazing travertine terraces.

This winter we have had only a handful of bright, sunny days. Not usual to have such continual overcast conditions. Even when the sun is out the hazy white clouds cover the entire sky giving us little of the sun’s warmth. But today is a glorious blue sky day, so let’s enjoy a walk around the Upper Terraces. Last year we snowshoed Upper Terrace Drive, remember? Open only to skis and snowshoes in the winter, but in summer it is a lovely drive. We have no snowshoes today, so we’ll stick to the boardwalk.

Ah, blue sky. It is about 18 degrees outside but with no wind and bright sun, it feels much warmer. The boardwalk on the Upper Terraces gets us close to the thermals that create the amazing terraces Mammoth is known for. Expelling the huge plume of steam to the left is Canary Spring which gushes much of the mineral-laden water that creates the steep terraces in this area. Too steamy today for a clear shot of the spring though.

Along the boardwalk we are close to these terraces which are always changing. The thermal activity at Mammoth is very different from that found in the geyser basins and other thermal areas further south in the park. Areas such as Old Faithful, Mud Volcano, and Lower Geyser Basin are the result of volcanic activity.  However, these formations are the result of thermal HOT water dissolving limestone from the significant limestone base under this entire area.

The water dissolves the limestone (calcium carbonate) then carries high amounts upward. As it reaches the surface, carbon dioxide is released and the calcium carbonate is deposited as travertine, a chalky white mineral that forms the rock of the travertine terraces. Because of the soft nature of limestone, the formations change faster than other type of thermal feature. These features not only  constantly changing, but change quickly. I’ve seen differences in the terraces after only being away a few months. Always amazing.

Here’s a closer look. The travertine envelops anything that lays in it path. This dead tree is already becoming part of the terraces.

A bit further down the boardwalk is a renewing feature–Cupid Spring. See on either side of the colorful area the gray flaking and breaking rock? Signs there is no active water on the already formed features–in essence they are dead. This was not active last year so seeing the water revitalizing the area is a treat. Alive again! The other great thing up here is the view on a clear day–the Absaroka Mountains straight ahead (north).

Well, we had the morning sun, but here we are again–overcast–sigh. Just a bit of sun peeking through, but the clouds are coming in strong. Let’s have some lunch and see what the terraces hold for us later this afternoon. After all, we are staying at the Mammoth Hotel tonight, so we have plenty of time to come up here again.

2PM: This morning we were looking at the terraces near the boardwalk. The water in those pools came from here, Grassy Spring. Don’t you love the trees and the community of life they support? You can see all the colors, not to mention the steam, coming from the spring.  The colors are, of course, thermophiles, heat-loving organisms.

A bit further down the boardwalk we see the spring’s water spreading across the area.  There’s the terraces we took photos of this morning. Yes, that is the extension of the boardwalk where we got a few shots. See the colors, all thermophiles in their winter coats. More yellow and orange in warmer weather.

Here we are, Canary Spring. Very hard to actually see and harder to photograph, but from up here we get the idea. Lovely blue pool in the white travertine.

I’m not any kind of weather expert, so I’m not sure why there is so little steam now allowing us to see Canary Spring. It is 25 degrees and certainly cold enough for huge amounts of steam, but lucky for us it is not happening.

Walking to the end of the boardwalk we are looking across the face of the travertine formation. Even in overcast conditions, the colors and the water pop. Getting a shot between steam plumes is the challenge. As the water pours over the edge, it forms “teeth” of travertine. Sometimes if the formation gets too heavy it breaks off and a new formation begins. The broken piece continues to grow and change, making a different pattern on the terraces.

The hardened travertine (whiter areas) have pools on their surface. If the discharged water changes direction or the “plumbing” removes the water from an area, the travertine turns gray and appears “dead” as we saw by Cupid Spring, but all is not lost. It could be only a matter of weeks or months and water will spring them to life again.

Well, the weather is only getting worse, so I think it is time to call it a day. We’ll try the walk again in the morning. Looking forward to a great dinner at Mammoth Dining Room. The smoked chicken linguine is to die for. I do love Mammoth.

7AM: Let’s get an early start. So far the weather looks totally overcast, but I’m sure I saw a promising speck of blue in the sky. Keep your fingers crossed.

Now that we have driven up almost 1,000 feet from Mammoth Hotel to the Upper Terraces, it is totally overcast and snowing. Sunrise isn’t until about 7:30, but it makes little difference this morning.  We had a few inches of snow last night and it is still snowing, although sideways. Common occurrence around here. Look, we are the first to walk on the new snow, not a footprint to be seen. That’s rare. Maybe dark and dreary encouraged a later start for folks.

Looking toward Grassy Spring, we are really socked in and it is snowing hard. This dead tree looks like a sci-fi crawling creature. Creepy don’t you think?

Oh, we do have a fellow traveler on snowshoes heading up the boardwalk. Grassy Spring is sending out its hot water as building material.

Snow on the sides of the trees by Grassy Spring. Can you tell is has been windy? No wind now which is nice. Wind is the game changer here. It can drop the temp almost instantly from a balmy 10 degrees to well below zero. Always dress in layers.

Cupid Spring with virtually no view today.

A new spring keeps getting bigger a bit further down the boardwalk. Its name is New Blue Spring–don’t ask me. Perhaps when the sun is out and temps are warmer it turns blue? That won’t happen today. Then again New Pea Green Spring doesn’t really have the same appeal.

From here we can see the village we know as Mammoth Hot Springs. It’s not snowing much up here now, but the haze below is snow. Red roofs grace Fort Yellowstone, the historic stone buildings built in 1909 and which the army used when they patrolled the park before the Park Service was created. The tan roof is the Mammoth Hotel, the brown roof Mammoth Dining Room and Terrace Grill. Behind the dining building are the cabins that are lodging options in the summer. Theres’ also a post office, police station, courthouse, and more. You can take a tour of the area with a ranger during the summer season.

Well I don’t know about you, but I want to head to breakfast. Looks like another snowy day, the wind is picking up, and I’m hungry.

Almost to the parking lot and surprise! There is hope yet. A trip to Lamar may be in the cards after breakfast. Winter in Yellowstone–weather can be crazy,  but always an adventure.

Until next time, think spring!