She told the conference: “80% of the people displaced in climate change globally are women.
“Addressing the rapidly changing climate is a matter of justice and equality, with the most vulnerable most affected, including indigenous communities, less-developed countries, and our focus today – and every day – on women.
“We come here fresh from advancing the most ambitious and consequential climate and clean energy legislation of all time in our country.”
She added that the US is doubling its financial commitments to climate change by the end of the year, with a focus on women's equality, adding: "We believe that when women succeed, the world succeeds."
When asked separately by journalists if President Joe Biden was doing "enough" to tackle global warming, she responded: "Absolutely. He's taken a lead and he's been in the lead since the '80s."
Ms Ocasio-Cortez also praised the president's climate agenda but added: "I think we need to do more."
The congresswoman said the US has yet to regain its moral authority on the climate discussion following Donald Trump’s presidency - including his withdrawal from the Paris climate agreement which Mr Biden reversed - but it is on the way to changing the tide.
"We have not recovered our moral authority, I believe we are making steps," said Ms Ocasio-Cortez.
“We have to actually deliver the action in order to get the respect and authority internationally. We have to draw down emissions to get credit internationally, it’s that simple.”
Ms Ocasio-Cortez shared details of her journey to Scotland on her Instagram, saying it was her first ever trip with a “codel” – congressional delegation.
She was among a group of more than 20 US politicians, led by Ms Pelosi, who said it was the largest congressional delegation to have ever attended a climate change conference.
They flew in from the US in a military aircraft, with Ms Ocasio-Cortez posting: “Despite the craziness and media frenzy, I was still a waitress just three years ago.
“So I still have moments in my life where it hits me that I’m actually in Congress. This was one of those moments.”
Posting a photo of the coronavirus test she took upon arrival in the UK, she said: “Shout out to the NHS, I wish we had you at home. We need #medicareforall.”
As discussions at the conference turned to issues of gender equality, a giant puppet called Little Amal arrived in the “blue zone”.
The 12ft-tall puppet, which represents a young Syrian girl, has walked 4,970 miles across Europe to raise awareness around the needs of refugee children.
It was present as a session on “advancing gender equality in climate action” began at the conference.
The event was designed to showcase some of the best examples of gender equality in climate action, highlighting the disproportionate impact of climate change on women.
On Tuesday, as part of the summit’s Gender Day, COP26 President Alok Sharma announced UK Government funding of £165 million for communities and women’s groups to tackle climate change.
Anne-Marie Trevelyan, the UK minister who is chairing the flagship Gender Day event, said: “It is women, girls and those who are already most marginalised, that will be most severely impacted by climate change.
“But they also have a critical role to play to address the climate crisis.
“The UK is committed to addressing this dual challenge head on, committing new funding to empower communities and women’s groups to take locally-led adaptation action, to build local, national and global resilience.”