Voter disapproval of the leadership change from Malcolm Turnbull to Scott Morrison has risen seven points in a fortnight, and Labor has maintained an election-winning lead over the Coalition in the latest Guardian Essential poll.

A fortnight on from the leadership bloodletting in Canberra, the latest survey of 1,050 voters has Labor in front of the Coalition on the two-party-preferred measure 54% to 46%, and the Coalition’s primary vote on 36%.

Morrison remains ahead of Bill Shorten on the better prime minister measure, 39% to 27%, with a large group, 34% undecided. In the poll taken immediately after the leadership fracas, Morrison had the backing of 39% (down 2% from Turnbull’s rating last month), while 29% backed Shorten.

The Guardian Essential sample remains divided about whether the leadership change should have happened, with 35% approving of Morrison replacing Turnbull and 47% disapproving – which is up 7% from the reading a fortnight ago.

Coalition voters are also split – 47% approved and 38% disapproved.

As well as taking on water from the ugly leadership fight, the poll also suggests the Morrison government is vulnerable on climate change.

The new prime minister has junked the emissions reduction component of the national energy guarantee – insisting the sole focus be on reducing power prices – and while the government says it remains committed to the Paris climate treaty, there are currently no concrete policies to ensure the requisite level of emissions reduction happens.

A solid majority of the sample, 69%, (including 62% of Coalition voters) believes that it is important the government agree to a policy for reducing carbon emissions to combat climate change. Just 23% say that’s unimportant.

In terms of voter approval for the two leaders, the prime minister’s outlook is more favourable. 37% gave Morrison a tick for the job he is doing as prime minister (down 5% from Turnbull’s figures last month), and 31% disapproved (down 11%) – which is a change in net approval rating from 0 to +6.

For Shorten, 35% approved of his performance (up 1% from last month), and 43% disapproved (down 1%) – which is an improvement in the Labor leader’s net approval rating from -10 to -8.

Voters were asked to rate the attributes of the two leaders. Morrison’s key attributes were intelligent (66%, but that figure is down 8% on Turnbull’s last reading), hard working (60%, no change) and a capable leader (54%, up 1%).

The opposition leader’s key attributes were hard-working (58%, which is down 2% since April), intelligent (55%, down 4%), out of touch with ordinary people (50%, no change), superficial (50%, up 3%) and arrogant (50%, up 7%).

When the attributes of the two leaders are compared, Morrison is more likely to be considered intelligent, a capable leader, more honest than most politicians and trustworthy – while Shorten is more likely to be considered erratic, arrogant and superficial.

While the data suggests voters have more favourable views about Morrison than Shorten, a series of questions in the latest survey underscores the deep frustration of voters with the instability in Canberra. Sixty-three per cent of the sample agreed with the statement: “I have lost trust in this government to function effectively and govern the country. Australia needs a new government”.

A majority, 60%, agreed with the statement: “The new prime minister was not elected by the people and has no legitimacy. He needs to go to an election as soon as possible.”

“A larger majority, 67%, agreed with the statement: “I’m sick of the major parties changing their leaders. I would consider voting for a third party to send a message to them both,” while 68% agreed with the statement: “Labor is the alternative government and I want to hear from them what their policies are – not what is wrong with the Liberal party.”

Leadership coups in the past have delivered the major parties an average bounce in the primary and two-party-preferred measures of 3%, according to that data.

This positive trend was consistent from Kevin Rudd to Julia Gillard, Gillard back to Rudd, and Tony Abbott to Malcolm Turnbull – so the switch to Morrison is the first time an incumbent government’s position has deteriorated as a consequence of a change.

Morrison is facing his first parliamentary week as prime minister, since the leadership change came right at the end of the last parliamentary fortnight.

Labor has trained its guns on the home affairs minister, Peter Dutton, who faces questions about the use of his ministerial powers in granting au pairs tourist visas, and with voters obviously uneasy about recent events, the opposition is pressing Morrison about why the leadership change happened.