Combating the terror threat, climate change and proportional representation lead the topics at the Green Party conference, which begins on Thursday.
Speakers will discuss Hurricane Katrina and other flooding risks.
The internationally-flavoured event boasts speakers from Africa, Japan, and West Papua among others.
The Greens had their best ever election result in May but still failed to gain a seat in parliament.
They will use the conference to call for a bigger Green voice in international and domestic politics.
The conference takes place St Martins College, Lancaster.
Opening the conference, Professor John Whitelegg, Green Party Sustainable Development Spokesperson and leader of the North West Greens, expressed the party's "deep concern" at the tragic events in America due to Hurricane Katrina.
"Hurricane Katrina must be seen as a stark warning to us all. What has become totally clear is that extreme weather kills, it may kill quickly," he told delegates.
"We must face the facts: If we don't put things right, we will see weather events on a par with Hurricane Katrina in the UK. Plans must be put into place, action must be taken now."
On Thursday Green Party London Assembly Member Jenny Jones joined by representatives from The Electoral Reform Society and Charter 88 for a discussion on the future of the electoral system in the UK.
"Our current electoral system is archaic and unrepresentative," she said, prior to the panel.
"Electoral reform is long overdue, especially for Westminster. Greens won a quarter of a million votes in the recent election, and won 22% of the vote in Brighton alone, but we still have no voice in Westminster."
"People need to know that their vote counts, that they can make a difference. Only a system of Proportional Representation genuinely offers this," she said.
The party will also discuss the UK's use of nuclear power as well as policy debates on intellectual property rights, open source software and domestic tradable quotas for carbon.
Speakers from civil rights group Liberty and the Campaign Against Criminalising Communities will be joining the terrorism panel discussions at the conference on Saturday.
A spokesman said: "Recent world events have provided us with a barrage of evidence that the 'business as usual' strategy employed by current world leaders, is not working.
"The Green Party are the only political party to provide a viable, sustainable alternative. Our message today is more important than ever."
The conference is due to open on Thursday by John Whitelegg, chairman of the North West Green Party, who is also an expert in climate change.
A party spokesperson said he will address the disaster caused by Hurricane Katrina and the possible flood issues facing the British Isles in the future.
In May's General Election, the Green Party contested 200 of the 646 seats. It won 1.07 of the popular vote and came third in Brighton Pavillion, doubling its share of the vote.