This year the UN marks its 70th anniversary. Sadly, there is little time for reflection or celebration. More pressing are the competing demands and challenges fuelled by an upsurge in conflict, disease and human suffering. These compel the international community to step up and provide the leadership needed to tackle them.

Ebola continues to plague west Africa. For some of the affected countries, struggling to overcome the effects of bitter civil war, the outbreak has been a major setback for development. We are beginning to see some improvements. During my visit to the region in December, I was deeply moved by the efforts of local Ebola responders and health workers from across Africa and the world. But rebuilding shattered lives and economies will require significantly more resources and long-term commitment.

As conflicts raged and extremism rose, 2014 pushed the UN’s humanitarian, peacekeeping and diplomatic efforts to the limit. More than 100 million people needed assistance. An unprecedented number of UN troops and police are deployed in highly volatile security environments.

The elimination of Syria’s chemical weapons programme was a major achievement, but the conflict continues to inflict immense suffering and will soon enter its fifth year. As bitter winter conditions set in, millions of refugees are in need of life-saving humanitarian assistance. The presence of thousands of foreign terrorist fighters there and in Iraq has added a further volatile dimension.

Groups responsible for atrocities have capitalised on a legacy of atrocious governance towards disenfranchised populations. Our response to brutality and extremism cannot be limited to military action, important as it is. We must address the conditions that give rise to such poison in the first place. In the same vein, those conducting military actions against terrorists must be sure that such efforts fully observe human rights. As we have seen time and again, failure to do so can end up serving as a recruiting agent for terrorists.

Elsewhere, the recent appalling terrorist attacks in Paris show how vulnerable any society can be. Countries in Europe and elsewhere have witnessed a deeply worrying escalation of tensions between communities and within societies. Giving in to hatred and sowing division only guarantees a spiral of violence – precisely what terrorists seek. We must not fall into that trap. Addressing discord in a manner that solves, rather than multiplies, the problem may be the greatest test our human family faces in the 21st century.

There is a long list of other hot-spots – stretching from Nigeria to Yemen, from the rise in fighting in Darfur to the transition in Afghanistan. Conflict in Ukraine has endangered security and stability in Europe, and reanimated the ghosts of the cold war. Israelis and Palestinians must ease the explosive situation in Gaza and the West Bank, and move away from confrontation and towards a negotiated settlement.

But in a year marked by turmoil, UN member states have also proposed an initial draft set of sustainable development goals that will guide anti-poverty efforts for the next generation. Further negotiations will begin this month and culminate at a special summit in New York in September with the adoption of a development agenda that can help tackle inequality, empower women and girls, and promote shared prosperity.

Climate action took on significant momentum with major announcements by the EU, the US and China, and a successful climate conference in Lima, Peru, that kept complex negotiations on track. We must aim high: for the adoption of an ambitious and universal agreement in Paris in December to keep the rise in global temperatures below the dangerous threshold of 2C.

Ours is the first generation that can end poverty, and the last that can take steps to avoid the worst impacts of climate change. In this 70th anniversary year in which we renew our commitment to the goals and principles of the UN charter, the international community must rise to the moment.