As the first anniversary of the war approaches on Friday, fighting is most intense in eastern Ukraine.
Authorities in Kyiv, including President Volodymyr Zelenskyy, have warned that a new Russian offensive is getting under way, and there are expectations that Ukrainian government forces are planning counterattacks in the coming spring – aided by new supplies of Western weapons.
The next six months will see the nature of conflict change significantly.
Both sides will push to take large amounts of territory and any offensive will cost that side dearly in terms of manpower.
It remains to be seen whether Ukraine will bring its new weapons to bear in a way that will make a difference, and whether Kyiv’s troops can cross the Dnieper river in the south and assault Russia’s network of defensive lines in this vital sector that is key to the war.
Russia, too, has to be seen to be winning, especially when so many lives are being sacrificed on the battlefield.
While its military is adapting, it is questionable whether it can change enough and adopt new ways of fighting before its armies are destroyed.
The loss of experienced Russian troops is being felt and it is now understood to be trying to rearm an increasingly citizen conscript military that might be more numerous, but less competent.
What’s happening now?
Despite a large influx of tens of thousands of new Russian conscripts, bolstered by units of airborne and marine infantry troops brought in from home bases near the Pacific Ocean, Moscow is still floundering in its push to retake Ukrainian towns in the eastern Donbas region.
Bahmut in Donetsk remains Russia’s focal point.
For months, Russia’s high command has extensively used Wagner Group mercenaries in the city, mainly convicts fighting for their freedom if they served in Ukraine.
Human wave attacks, rarely effective in World War I, proved disastrous for the group.
So total was the destruction that Russian prisoners refused to volunteer, the prison recruitment programme was shut down, and Wagner Group units were pulled from the front lines.
Further south, Russia’s offensive to take Vuhledar has met equally fierce resistance.
Russian armoured units were wiped out as a combination of Ukrainian artillery, clever mine emplacement and direct fire blunted attack after attack.
How do changes in the weather affect war?
Most Russian attacks have taken place while the ground was hard and the temperatures sub-zero.
Within a month though, this will change.
A long period of rain will turn previously easily traversable fields into muddy quagmires, slowing movement to a crawl.
This will not stop Russian attacks but it will force armour and infantry to keep to roads if they want to move quickly, making them easier to target and destroy.
Wet weather would also affect any Ukrainian offensive planned for the spring.
The south has been carefully fortified by Russian forces and Ukrainian troops would have to move swiftly over the wide open spaces of the region to avoid destruction out in the open.
Deep mud and rain would hamper those efforts.
Where are the pledged Western tanks?
Newly promised Western tanks will take time to arrive in any numbers that would make a difference to the outcome of the war.
Ukrainian crews need training if they are to leverage the higher quality optics and software that give tanks like the Leopard 2, Challenger 2 and Abrams such an advantage in battle.
Ukraine is increasingly adopting Western digital mechanised logistics and warehousing.
And it will need to, the increase of foreign weapons systems in Ukraine means keeping them running as effective military tools is as vital as training the tank crews.
While they can be powerful weapons, if tanks lack fuel, spare parts or ammunition, they will become next to useless and can be easily destroyed on the battlefield.
What are the dangers of a long war?
The conflict does not look like it will end any time soon. Both Ukraine and Russia insist on victory conditions that are unacceptable to the other.
Russia will not retreat unless forced to, Ukraine is unwilling to cede territory it has lost in the conflict and both sides say possession of Crimea by the other is a non-starter.
President Zelenskyy has been clear that the war will continue till every part of Ukraine has been retaken.
President Vladimir Putin is also aware that Crimea provides Russia with its only permanent warm water port, home to the powerful Black Sea Fleet at Sevastopol.
With compromise unlikely, other factors will start to play out.
The ever-present possibility of Western donor fatigue will rise as NATO members contend with rising energy costs, increased defence budgets, and assistance given to allies such as Turkey over its devastating earthquake.
If Ukraine is to prevail, a steady and increasing stream of high-tech weapons, ammunition, training centres and, in the long run, Western tanks and probably fighter jets, will be vital.
Billions of dollars need to be spent and NATO’s pockets, while deep, are not limitless.
As the conflict drags on, Russia’s military will start to adapt and learn from its many mistakes.
Does Russia have the advantage?
Russia has a long history of initial military failures, complete with incompetent leadership, poor training and bad equipment.
The 1939 Soviet invasion of Finland ended in less than four months and was followed by disastrous battles when Germany invaded the Soviet Union.
The war in Chechnya was a disaster for Russia in the beginning, but in each case, Moscow took the losses, learned from mistakes and fought better and harder – eventually overwhelming its opponent.
Russia has a larger industrial base now and a much larger population to draw conscripts from than Ukraine.
Its economy is not yet on a war footing, although moves have been made to increase weapons production.
It can replace losses in manpower more readily than Ukraine, with its smaller population.
Tactics are changing, too.
In early February, for the first time, what appeared to be a surface kamikaze boat drone damaged a bridge in Ukraine.
It was Russian, showing Moscow has built and deployed weapons that only Ukraine had used.
Fast speedboats now accompany and protect Russian naval vessels in the Black Sea, ensuring they are not the targets of boat drones themselves.
Playing to the strengths of conscripts who are best used in defensive operations, large intricate lines of trenches and fortifications have been built by the Russian army in the south.
The flat featureless terrain will provide little cover for an attacking force and Ukrainian units will first have to cross the Dnieper river in the kinds of numbers that will make a difference to an offensive.
Russia intends to make Ukraine fight for every metre of territory. Ukraine does, too.
In a battle of attrition that drags on, Russia may well have the advantage in terms of manpower, since it can dramatically increase the size of its armed forces.
Its industrial base is intact and well-funded while Ukraine has lost important sources of coal, steel and other supplies vital for war.
The continued damage to Ukraine’s energy infrastructure not only makes the lives of Ukrainians miserable. Factories cannot be powered and steel cannot be smelted as industry falters and the country relies increasingly on foreign imports and goodwill.
