Traveling is amazing. It allows me to leave the daily routine behind and gives me time to just slow down and think. My road trip in the South Island of New Zealand was not only eye-opening but mind-opening. The breathtaking landscape inspired me and had me opened myself up to new perspectives on life.
Leaving our homestay in Tekapo, we continued our expedition towards the south along the Southern Alps. There are seven major lakes in the South Island that offer truly awe-inspiring views, and each of them has their own identity. Queenstown lies in the middle of Lake Wakatipu; Lake Wanaka is popular with two major ski fields; Lake Tekapo is a great spot for star gazing at the mountainside Mount John Observatory; Lake Ohau offers incredible mirror images of the Southern Alps; Lake Te Anau leads to the magnificent Milford Sound; Lake Hawea is a great place for activities like kayaking, windsurfing, fishing, and boating; and that morning we drove along Lake Pukaki. The lake is famously known as the ‘Lake-town’ in ‘The Hobbit: The Desolation o Smaug.’ The lake also leads to Mount Cook (the highest peak in the Southern Alps) and Tasman Glacier (New Zealand’s largest glacier), which was our destination for the day.
Lake Pukaki, and why is it baby-blue?
Lake Pukaki has a distinctive, iridescent baby-blue color. Why? When the glaciers move through the valleys they grind and crush the brittle Sandstone, Greywacke and Schist rocks. This creates a fine powder known as ‘Glacier Rock Flour’ which is suspended in the water in high concentrations and empties into Lake Pukaki where it mixes with the fresh water of the lake. The heavy rock flour particles sick to the bottom and only the very fine particles are left floating in suspension. As light penetrates into the lake all the colors of the light spectrum are absorbed, except the baby-blue. This color refracted off the tiny particles of rock flour gives Lake Pukaki its unique identity. Check the lake out on the Google Map, you will see the color of the lake stands out from the rest of its neighboring bodies of water.
Tasman Glacier and a face-to-face with the Terminal Face
It was exciting to see the highest peak in the Southern Alps and visit the largest glacier in a day. It was not my first time visiting a glacier – I visited Folgefonna in Norway, and had fun Glacier Hike (Visit: Glacier Hiking: Folgefonna!); and Jökulsárlón in Iceland, and had a taste of the thousand-year-old glacial ice! (Visit: On the Tip of Your Tongue: Jökulsárlón). It was, though, my first time going to a glacier in the southern hemisphere; More, we hopped on a boat this time and view the glacier in the water. There are several glaciers in the Southern Alps, including the Mueller Glacier, Hooker Glacier, Franz Josef Glacier and Fox Glacier… while the Tasman Glacier, with its length of 23.5 km, is the largest in New Zealand.
We reached the Hermitage Hotel early in the morning and it’s a pitstop and gathering point for the tours and expeditions in Mount Cook. We signed up for a Glacier Explorers Tasman Glacier tour and after a short bus ride and a short walk through the trails, we started to board the boats at one end of the glacier. The tour guide would take us up to the Terminal Face, and on the route, we saw the beautiful blue ice and breathtaking mountain ranges on both sides of the glacier. The weather was unstable and we were caught in a downpour right after we got on the boat. Luckily, the rain stopped for the rest of the trip and we could enjoy the beautiful glacier under the sun, and we got to see a rainbow straddle across the mountain as we were leaving.😊
How the Tasman Glacier is formed?
I was not surprised to learn that glaciers have been shaping and reshaping the landscape of the Southern Alps for the last 2 million years. The Tasman Valley that we were in was carved by the Tasman Glacier over 18 thousand years ago during the ice age. The glacier was at it’s largest 18 thousand years ago, and it was 200m above and 400m below the current valley floor and over 100km long. It was until 13 thousand years ago the earth started to warm and the glacier started to retreat. As the ice melted, the suspended debris, which was scooped up by the glacier earlier, deposited once again. In the Tasman Valley, this is known as TILL. The depth of the current valley is 400m of TILL left by the by the retreating Tasman Glacier.
The beginning of the glacier, known as the Neve, is at 2300m above sea level. The Neve receives 20 to 30 of snow annually, which compacts down under its own weight to form around 7m of glacial ice. The Glacier then flows downhill for 17km until it comes up against the Mount Cook range, and then it takes a sharp left turn and flows for another 7km before terminating at the Tasman Lake – this 7km of the glacier is visible from the lake, where our boat was. The first 17km of the Tasman Glacier is pristine and white, while the last 7km is covered in a rock mantle – which also known as the Melt Line. The upper ice there melted away to expose the Moraine that was once frozen inside.
It was amazing that although it sounded simple, it was a long process. Snow falling in the Neve takes about 300 to 600 years to move its way through the glacier and finally end up in the Tasman Lake – which means, the icebergs that I saw in the lake began as snow more than 300 years ago!
The Glacial ice is made up of millions of tiny ice crystals, and it is extremely dense (due to the weight and pressure and it got compacted down over many, many years). So, the iceberg that we saw has a distinctive ‘steel blue’ color (with intricate crystalline patterns), as it absorbs all colors of the light spectrum, except the color with the shortest wavelength – blue. As the sun penetrates into the ice, it warms the gases that trapped inside. The gas expands and causes the ice separate into individual ice crystal (Science is fun!). The ice will eventually turn white in a short period of time as the light bounces between the crystals.
The Terminal Face of the Tasman Glacier is fixed to the valley floor, rather than floating like an iceberg. The Terminal Face is currently in a melting and calving face, which means ice would fall into the water as it melts and breaks off from the glacier, producing icebergs. We approached the Terminal Face yet we couldn’t get too close before ice could be collapsing any time, and even the ice didn’t hit us, the current that formed as the ice sank would suck us into the water – and the Terminal Face actually descends for more than 200m underwater!